p-issn; 1411-9420; e-lssn: 2460-1578 indonesian journal of...

p - I S S N ; 1 4 1 1 - 9 4 2 0 ; e - l S S N : 2 4 6 0 - 1 5 7 8

Indonesian Journal of Chemistry A c c r e d i t e d b y D I K T I N o : 5 8 / D I K T I / K e p / 2 0 1 3

Scoffs No : 6 2 8 / U C / 0 5 / 7 0 1 6 S u b j e c t : Result of Review Manuscr ip t ID No. 2016-02-915 E n d . : 2

Yogyakarta, 3 May 2016

Dear Ms. Agus Setiabudi.

Department of Chemistry, Univers i tas Pendidikan Indonesia. JL Dr. Set iabudhi 229 , Bandung 40154, Indonesia

This is to acknowledge and in form you that the paper entit les:

M i c r o s c o p i c O b s e r v a t i o n o f S o l i d - L i q u i d R e a c t i o n ; A N o v e l L a b o r a t o r y A p p r o a c h to T e a c h i n g R a t e

Agus Setiabudi, Asep Wahyudin, Calub Yutiani, and Mauro Mocer ino

has been rev iewed and could be publ ished in Indones. J. Chem. af ter major rev is ion. The author should make some correct ion as fol lows:

R E V I E W E R I: 1 P lease follow Indones. J . Chem. authors manua l template. 2 Abstract and keyword in Indonesian language should be added. 3 In this manuscript , 2D images of MgO were assumed to be proport ional to i ts mass . However it really depends on

regularity of MgO shape. Can this method be applied to MgO wi th 3D irregular shape. A Validity of this method need to be enhanced R E V I E W E R II 1 Car a penul isan re ference; contoh: X . -S . Fang > Fang, X . S ; perlu dicek kembal i tahun 2. Cara penyaj ian tabe l ; contoh table 3, baris antara 0-200 tidak bergaris. 3. Di abstrak dan pembahasan solid hanya MgO (kecuali tabel 4 ) , tetapi di mater ia l dan t a b e l 1 ada Zn, Fe dan C a . 1. Beberapa kata di dalam keywords tidak ada di dalam abstrak Addit ional notes from editor: Please present the manuscr ipt in complete sentences in paragraph rather than using points or number (page 6 & 10) ; Engl ish abstract max. 700 words wi th 5 keywords ; p lease add up-to-date ref (a 2006) unti l n 80% total re ferences, w i th min imum re ference are 15 .

Please kindly send your revised manuscr ipt by May 1 7 9 1 2016, so that the art ic le could be publ ished in the upcoming Indones. J. Chem. Also k indly send your response to the rev iewers ' comments (each point ) in a separa te letter. Thank you for your submission and w e are wait ing for the other art ic les from you and your col leagues.

S incew ly yours,

Prof. DiV Nuryono, M 5 Editor in Chief

Department of Chemistry , Univers i tas Gadjah Mada S e k i p U la ra Yogyakar ta 55281 P h o n e / F a x +62-274-545188 E m a i l : nu r yono_n ipa@ugm ac . i d / i j c@ugm.ac . i d (for article submiss ion)

o f R e a c t i o n

wr i t ten by:

MICROSCOPIC OBSERVATION OF SOLID-LIQUID REACTION;

A NOVEL L A B O R A T O R Y A P P R O A C H TO TEACHING R A T E OF REACTION

A g u s S e t i a b u d i 1 ' , A s e p W a h y u d i n 1 , G a l u h Y u l i a n i 1 , a n d M a u r o M o c e r i n o 2

1 D e p a r t e m e n t o f C h e m i s t r y , U n i v e r s i t a s P e n d i d i k a n I n d o n e s i a , d e p a r t m e n t o f C h e m i s t r y , C u r t i n U n i v e r s i t y ,

1 C o r r e s p o n d i n g a u t h o r : J i . Dr . S e t i a b u d h i 2 2 9 , B a n d u n g 4 0 1 5 4 , I N D O N E S I A E - m a i l : a g u s s e t i a b u d i @ u p i . e d u

2 ) C o - a u t h o r s : J I . Dr . S e t i a b u d h i 2 2 9 , B a n d u n g 4 0 1 5 4 , I N D O N E S I A E - m a i l : q a l u h ( S ) u p i . e d u E - m a i l : a w a y @ u p i . e d u

2 ) C o - a u t h o r 2 : G P O B o x U 1 9 8 7 , P e r t h , W e s t e r n A u s t r a l i a 6 8 4 5 , A u s t r a l i a E - m a i l : m . m o c e r i n o @ c u r t i n . e d u . a u

Abstract T h e impor tance of observa t ion in s c i e n c e and s c i e n c e educat ion h a s tr iggered this laboratory deve lopment s tudy that invest igated the va lue of a n observat ion kit a s a n e w approach to teaching rate of react ion in genera l chemis t ry c l a s s . T h e kit c o n s i s t s of a digital m ic roscope, a "chemica l reactor", a n d a ta i lo r -made computer appl icat ion and w a s used to v ideo-record a solid-liquid react ion a n d to produce a s e r i e s of two d imens iona l solid i m a g e s that indicate the extent of react ion. T h e two d imens iona l i m a g e a r e a s w e r e ca lcu la ted by the computer appl icat ion by a s s u m i n g that the image a r e a w a s direct ly proport ional to the sol id m a s s from wh i ch a plot of m a s s v e r s u s time could be obta ined. T h e s e s t e p s h a v e been tested to sol id ( z inc , iron, ca l c ium carbona te , and m a g n e s i u m oxide)- l iquid (ac id solut ion react ion s y s t e m s . Reac t ion of sol id m a g n e s i u m ox ide with nitric a d d solution resu l ted in the best i m a g e s wh ich w e r e t ransferab le to a plot of sol id m a g n e s i u m oxide m a s s a s a funct ion of t ime. T h i s w a s used to exp la in rate of react ion c o n c e p t s including a v e r a g e , i ns tan taneous , a n d initial rate. Fur thermore , the effect of concentrat ion on react ion rate could a l so be exp la ined . T h e genera ted da ta a l l ows s tudents to d e a r l y a n d repeatedly v i sua l i ze a solid-liquid react ion a n d re la tes ra tes of react ion concep ts . T h e observat ion kit a l so a l lows t e a c h e r s a n d s tudents to ex tend its appl icat ion into inquiry b a s e d exper imen ts .

K e y w o r d s : M i c r o s c o p i c o b s e r v a t i o n , so l i d l iquid r e a c t i o n , r a t e o f r e a c t i o n , inqu i ry l ea rn i ng

A b s t r a k Penel i t ian p e n g e m b a n g a n perangkat dan keg ia tan laborator ium ini d idasar i oleh pen l ingnya obse rvas i d a l a m s a i n s d a n pendid ikan s a i n s . Pe rangka t p e n g o b s e r v a s i r eaks i kimia yang d i kembangkan dapat d igunakan d a l a m perku l iahan laju reaks i d a l a m k e l a s k imia dasa r . Dar i s e r a n g k a i a n reaks i k imia y a n g diuji c o b a , reaks i an ta ra padatan m a g n e s i u m o k s i d a dengan larutan a s a m nitrat berhas i l membe r i kan data berupa image y a n g dapat diolah menjad i informasi kinetik. B e r d a s a r k a n m a s s a MgO sebe lum reaks i , da ta image partikel y a n g d iperoleh da lam video diubah men jad i da ta m a s s a . s e h i n g g a diperoleh plot m a s s a m a g n e s i u m oks ida ebaga i fungsl wak tu . Dar i da ta yang d ipero leh, m a h a s i s w a d iperkena lkan pada k o n s e p laju r e a k s i , penen tuan nilai la ju, d a n pengaruh konsen t ras i t e rhadap laju reaks i dan orde reaks i . S e t da ta yang d iperoleh memungk inkan m a h a s i s w a untuk s e c a r a v i sua l mengamat i reaks i pada tan dengan c a i r a n d a n menghubungkannya dengan k o n s e p laju reaks i . Pe rangka t pengobse rvas i ini j uga , berpe luang untuk d i in tegras ikan dan d i k e m b a n g k a n n y a k e da lam pembe la ja ran be rbas i s inkuir i .

K a t a k u n d : P e n g a m a l a n mikroskopik . reaks i padat-cai r . laju r e a k s i , pembe la j a ran inquiry

Introduction

T h e u s e of i n -s i tu o b s e r v a t i o n i n s t r u m e n t s to s t u d y v a r i o u s c h e m i c a l p r o c e s s h a s

g a i n e d m u c h a t ten t ion for a l ong t ime . O n e e x a m p l e i s the u s e of E n v i r o n m e n t a l S c a n n i n g

E l e c t r o n M i c r o s c o p y ( E - S E M ) to o b s e r v e h e a t - i n d u c e d c h a n g e in m a t e r i a l c h e m i s t r y [1 ] ,

A n o t h e r s t u d y [2] u s e d a n o p t i c a l m i c r o s c o p e to i n v e s t i g a t e t he t y p e of i n te rac t i on b e t w e e n

t h e c a t a l y s t m a t e r i a l ( C s 2 S 0 4 V 2 0 5 ) a n d s o o t m a t e r i a l ( m a i n l y c a r b o n ) f r o m r o o m

t e m p e r a t u r e to 3 5 0 ' C . B y u s i n g s u r f a c e p l a s m o n s p e c t r o s c o p y , a c h e m i c a l r e a c t i o n on t h e

s u r f a c e o f a n a n o - s i z e d g o l d pa r t i c l e w a s o b s e r v e d [3 ] .

T h o s e repo r t ed r e s e a r c h a c t i v i t i e s a r e g o o d e x a m p l e s that s h o w e d t h e i m p o r t a n c e of

s c i e n t i f i c o b s e r v a t i o n in s c i e n c e i n v e s t i g a t i o n w h i c h i s v e r y impo r tan t for bo th s c h o o l a n d

a l w a y s o n h a n d a t m a n y u n i v e r s i t i e s , for t he s a k e o f u n d e r g r a d u a t e c h e m i s t r y c l a s s r o o m s ,

t h e s e s c i e n t i f i c o b s e r v a t i o n a c t i v i t i e s c o u l d b e r e p l i c a t e d in s i m p l e r a n d c h e a p e r e q u i p m e n t

S i m p l i f i e d r ep l i ca t i on o f e q u i p m e n t o r r e s e a r c h i n s t r u m e n t s to b e c o m e a c l a s s r o o m

d e m o n s t r a t i o n d e v i c e h a s b e e n c a r r i e d ou t b y m a n y c h e m i s t r y e d u c a t o r s [4J—{11]. O n e

e x a m p l e i s a h o m e m a d e s p e c t r o p h o t o m e t e r t ha t c a n b e m a d e of i n e x p e n s i v e c o m p o n e n t s

[4 ] . T h i s s imp l i f i ed s p e c t r o p h o t o m e t e r c o n s i s t s of, a m o n g o t h e r s , flaslight a s a l ight s o u r c e ,

a c o m p a c t d i s c a s a d i f r ac to r ne t , a n d a n L D R a s a de tec to r O t h e r e x a m p l e s of d e v e l o p i n g

s i m p l e e q u i p m e n t a r e v i s i b l e l ight s p e c t r o m e t e r for u s e in s e c o n d a r y s c h o o l [5 ] a n d a

p h o t o c h e m i c a l r e a c t o r u s e d for f i ve o r g a n i c p h o t o c h e m i c a l l a b o r a t o r y e x p e r i m e n t s [6 ] . T o

d e m y s t i f y t he a p p l i c a t i o n o f e l e c t r o c h e m i s t r y in s e n s o r e q u i p m e n t , a s i m p l e o x y g e n s e n s o r

d e v i c e u s i n g z i n c - a i r e l e c t r o c h e m i c a l c e l l s w a s d e v e l o p e d [ 1 1 ] . T o p r o v i d e p h o t o c h e m i c a l

l a b o r a t o r y e x p e r i m e n t s , a n i n e x p e n s i v e a n d c o m m e r c i a l l y a v a i l a b l e u l t rav io le t l ight d e v i c e ,

i n t e n d e d for " d r y i n g " g e l - t y p e f i nge rna i l p o l i s h , w a s d e v e l o p e d by a g r o u p o f r e s e a r c h e r s

I

[ 1 2 ] . T h e f u n d a m e n t a l s o f U V s p e c t r o s c o p y , d a t a h a n d l i n g , ca l i b ra t i on , a n d s a m p l i n g , c a n

b e l e a r n e d b y s t u d e n t to m e a s u r e d i s s o l u t i o n r a t e s o f t a b l e t s [ 7 ] ,

In t h i s p r e s e n t s t u d y , w e d e v e l o p a n o b s e r v a t i o n kit tha t c a n b e u s e d for c h e m i c a l

k i n e t i c s e x p e r i m e n t s s p e c i f i c a l l y for t h e t e a c h i n g o f r e a c t i o n ra te . T h e l o g i c a l f r a m e w o r k for

t h e d e v e l o p m e n t o f t h i s s i m p l e e q u i p m e n t i s p r e s e n t e d in F i g u r e 1 .

T h e ki t c o n s i s t s o f a d ig i ta l m i c r o s c o p e , a " c h e m i c a l r eac to r " , a n d a t a i l o r - m a d e c o m p u t e r

a p p l i c a t i o n . T h i s w a s u s e d to v i d e o - r e c o r d a so l i d - l i qu id r e a c t i o n to p r o d u c e a s e r i e s o f t w o

d i m e n s i o n a l i m a g e s of t h e s o l i d tha t i n d i c a t e t he e x t e n t o f r e a c t i o n . T h e t w o d i m e n s i o n a l

i m a g e a r e a s w e r e a s s u m e d to b e d i rec t l y p r o p o r t i o n a l to s o l i d m a s s a n d w e r e c a l c u l a t e d by

t he c o m p u t e r a p p l i c a t i o n to p r o d u c e the a r e a s o f t h e c a p t u r e d i m a g e s to t i m e d a t a s e r i e s .

T h i s p r e s e n t a r t i c l e a l s o r e p o r t s t he t e s t r e s u l t s o f t he kit for o b s e r v i n g so l i d - l i qu id r e a c t i o n s

a n d the i r d a t a p r o c e s s i n g r e s u l t s . T h e d a t a o b t a i n e d w e r e e v a l u a t e d for the i r re l iab i l i ty

b a s e d o n the i r su i tab i l i t y w i t h t h e r e a c t i o n r a t e t h e o r y a n d the i r f eas ib i l i t y to u s e in t h e

l e a r n i n g p r o c e s s o f r e a c t i o n r a t e s .

M a t e r i a l s a n d m e t h o d s

T o i m p l e m e n t t he f r a m e w o r k , t h r e e m a i n a c t i v i t i e s w e r e c a r r i e d out : ( a ) d e v e l o p i n g o f

a n o b s e r v a t i o n kit for so l i d - l i qu id r e a c t i o n , ( b ) d e v e l o p i n g t h e a p p l i c a t i o n for p r o c e s s i n g

o b s e r v a t i o n d a t a , a n d ( c ) t e s t i n g a n d i m p r o v i n g t h e ki t a n d i ts c o m p u t e r a p p l i c a t i o n . T h e

re l iab i l i ty o f t he d a t a w a s t e s t e d b a s e d o n the i r f eas ib i l i t y to u s e in r e a c t i o n r a te a n a l y s i s

a . M a t e r i a l s

F o r t he so l i d - l i qu id r e a c t i o n s t e s t e d , t he s o l i d m a t e r i a l s w e r e z i n c , i r on , c a l c i u m

c a r b o n a t e a n d m a g n e s i u m o x i d e a n d the l i qu ids w e r e h y d r o c h l o r i c a c i d ( 2 M ) a n d n i t r i c a c i d

( 1 M a n d 2 M ) . A l l c h e m i c a l s w e r e p u r c h a s e d f r o m M e r c k

3

b. K i t a n d its o b s e r v a t i o n p r o c e d u r e

T h e o b s e r v a t i o n kit c o n s i s t s o f a d ig i ta l m i c r o s c o p e e q u i p p e d w i th a petr i d i s h that w a s

u s e d a s c h e m i c a l r e a c t o r w h i c h i s s c h e m a t i c a l l y p r e s e n t e d in F i g u r e 2 . T h e digi tal

m i c r o s c o p e w a s c o n n e c t e d to a c o m p u t e r tha t v i d e o r e c o r d e d the c h e m i c a l r e a c t i o n . T h e

so l id - l iqu id r e a c t i o n w a s c a r r i e d ou t by put t ing a b o u t 1,5 m g so l i d in a petr i d i s c . I ts init ial

a p p e a r a n c e a n d s i z e w e r e t h e n r e c o r d e d . S u b s e q u e n t l y , 5 m L a c i d so lu t i on w a s p o u r e d

in to t he petr i d i s h a n d t h e d ig i ta l m i c r o s c o p e i m m e d i a t e l y s t a r t e d to r e c o r d t he p r o c e s s .

c A p p l i c a t i o n for p r o c e s s i n g o b s e r v a t i o n d a t a

F o r e a s y t r a n s f o r m a t i o n o f a s o l i d g r a i n i m a g e to m a s s d a t a , a s o f t w a r e app l i ca t i on to

p r o c e s s o b s e r v a t i o n v i d e o s o f c h e m i c a l r eac t i on into k i n e t i c d a t a w a s d e v e l o p e d T h e

a p p l i c a t i o n h a s f e a t u r e s a n d d a t a p r o c e s s i n g s t e p s a s s u m m a r i z e d in F i g u r e 3 A s s h o w n

in t he f i gu re t he m a i n s t e p s in d a t a p r o c e s s i n g a r e to c a p t u r e i m a g e a t g i v e n t i m e i n t e r v a l s ,

to c a l c u l a t e i m a g e a r e a b y c o m p a r i n g t h e n u m b e r o f p i x e l s , to t h e n c a l c u l a t e t he so l i d m a s s

a n d plot it a s a f u n c t i o n o f t i m e .

R e s u l t s a n d d i s c u s s i o n

a . S o l i d - l i q u i d r e a c t i o n o b s e r v a t i o n t e s t

T h e o b s e r v a t i o n kit w a s a p p l i e d to s e v e r a l so l id - l iqu id r e a c t i o n s n a m e l y ; z i n c -

h y d r o c h l o r i c a c i d , i r o n - h y d r o c h l o r i c a c i d , c a l c i u m c a r b o n a t e - h y d r o c h l o r i c a c i d a n d

m a g n e s i u m ox ide -n i t r i c a c i d r e a c t i o n s . T h e r e s u l t s a r e s u m m a r i z e d in T a b l e 1 , w h i l e

e x a m p l e s o f c a p t u r e d i m a g e a r e s h o w n in F i g u r e 4 .

R e a c t i o n b e t w e e n z i n c a n d h y d r o c h l o r i c a c i d r e s u l t e d in g r a i n i m a g e s w h i c h w e r e

d i f f icu l t to a n a l y z e . A s c a n b e s e e n in F i g u r e 4 ( a ) g a s b u b l e s w e r e e v o l v e d f rom t h e z i n c

s u r f a c e c a u s i n g d i f f i cu l t i es in d e t e c t i n g s o l i d i m a g e b o u n d a r i e s . F u r t h e r m o r e , t he z i n c s i z e

4

c h a n g e s w e r e h a r d l y o b s e r v e d for a l ong r e a c t i o n t ime . S i m i l a r r e s u l t s w e r e s h o w n b y t he

r e a c t i o n b e t w e e n i ron a n d h y d r o c h l o r i c a c i d . A n o t h e r t y p e of r e s u l t s w e r e s h o w n b y t h e

r e a c t i o n b e t w e e n c a l c i u m c a r b o n a t e a n d h y d r o c h l o r i c a c i d w h e r e the g r a i n w a s sp l i t t ed in to

s e v e r a l p a r t s r e s u l t i n g in d i f f i cu l t i es for i m a g e a n a l y s i s . T h e r e f o r e t h e r e s u l t s o f z i n c , i ron ,

a n d c a l c i u m c a r b o n a t e c o n t a i n i n g r e a c t i o n s y s t e m wi l l not b e d i s c u s s e d fu r ther .

P r o m i s i n g r e s u l t s w e r e p r o d u c e d b y t he r e a c t i o n b e t w e e n so l i d m a g n e s i u m o x i d e a n d

ni t r ic a c i d . T h i s r e a c t i o n p r o d u c e d i m a g e s w i t h r e l a t i v e l y c l e a r s h a p e s a n d s o l i d b o u n d a r i e s .

T h e s c r e e n s h o t s o f t he M g O - H N 0 3 r e a c t i o n o b s e r v a t i o n a r e s u m a r i z e d in T a b l e 2 . In t h i s

e x p e r i m e n t , 1.5 m g of s o l i d M g O ful ly r e a c t e d w i t h 5 m L of 2 M H N 0 3 i n 3 1 2 s . T h e

o b s e r v a t i o n s c r e e n s h o t s o f t h e r e a c t i o n d u r i n g 3 1 2 s r e a c t i o n t i m e a r e h i gh l i gh ted in T a b l e

2 . A s c a n b e s e e n in t he t a b l e , a n a p p r o x i m a t e l y 2 m m s i z e g r a i n o f M g O d e c r e a s e d w i t h i n

1 m in t i m e . T h i s d e c r e a s e c o n t i n u e d fu r ther unt i l t h e so l i d M g O w a s c o m p l e t e l y r e a c t e d in

3 1 2 s .

S m a l l b u b b l e s w e r e st i l l s e e n in t h e r e a c t i o n b e t w e e n m a g n e s i u m o x i d e a n d 2 M n i t r i c

a c i d , p r o b a b l y c a u s e d b y t h e r e a c t i o n o f t he a c i d w i th s m a l l a m o u n t s o f m a g n e s i u m

c a r b o n a t e i m p u r i t i e s ( th i s c o u l d r e s u l t f r o m i n c o m p l e t e c a l c i n a t i o n o f m a g n e s i u m c a r b o n a t e

du r i ng m a n u f a c t u r e , or r e a c t i o n o f t he M g O w i t h c a r b o n d i o x i d e in t he a t m o s p h e r e ) .

T h e s e r e a c t i o n o b s e r v a t i o n s p r o v i d e c h e m i c a l k i n e t i c s i n fo rma t i on w h i c h i s v e r y u s e f u l l

for l e a r n i n g r e a c t i o n r a t e s . T h e i n f o r m a t i o n c a n b e s u m m a r i z e d a s f o l l o w s :

a . T h e o b s e r v a t i o n s s h o w e d t ha t a c h e m i c a l r e a c t i o n o c c u r e d in t h e s y s t e m a s i n d i c a t e d

by t he s o l i d M g O s i z e d e c r e a s e s .

b. T h e t i m e for M g O to r e a c t w i t h H N 0 3 r e f l ec t t h e r e l a t i v e r e a c t i o n ra te . T h e h i g h e r t he

c o n c e n t r a t i o n o f a c i d , t h e f a s t e r i s t he r a te o f t he so l i d - l i qu id r e a c t i o n .

5

c . If t he r e m a i n i n g so l i d M g O a t a t i m e i n te rva l i s a s s u m e d to pos i t i ve l y c o r r e l a t e w i t h g r a i n

v o l u m e , t h e n it i s d i rec t l y p ropo r t i ona l to t h e s u r f a c e a r e a o f t he s o l i d . T h e r e a c t i o n r a te

i s c o m p a r a b l e to t h e d e c r e a s e d a r e a o f t he i m a g e p e r t ime unit tha t c a n b e ident i f ied

u s i n g e q u a t i o n 1 .

( *JT=-^) o )

W h e r e : m M o 0 = m a s s o f M g O , A M g o = a r e a of i m a g e s , a n d t = r e a c t i o n t i m e

H o w e v e r , t h e a c c u r a c y o f t h i s m e t h o d w o u l d rea l l y d e p e n d on t h e regu la r i t y of M g O s h a p e .

T o i m p r o v e a c c u r a c y . a m o r e s o p h i s t i c a t e d a s s u m p t i o n s h o u l d b e a p p l i e d a s in rea l i t y M g O

h a s t h r e e d i m e n s i o n a l r e g u l a r i t i e s . T h i s r e f l e c t s t he l imi tat ion of t he m e t h o d ,

b. T h e F u n c t i o n a l i t y o f d a t a p r o c e s s i n g app l i ca t i on for o b s e r v a t i o n r esu l t

T h e m a i n f u n c t i o n o f t h e bui l t a p p l i c a t i o n i s to e x t r a c t t he i m a g e s f r o m the v i d e o a n d

s u b s e q u e n t l y c a l c u l a t e t h e i r a r e a . A n e x a m p l e o f so l i d M g O a n d H N 0 3 r e a c t i o n i m a g e a n d

v i d e o e x t r a c t s b e i n g p l a y e d i s s h o w n in t he s c r e e n s h o t o f t he a p p l i c a t i o n in F i g u r e 5 . T h e

left h a n d s i d e par t i t ion s c r e e n in F i g u r e 5 , s h o w e d the e x t r a c t e d M g O pa r t i c l e i m a g e s a t

s e v e r a l po in t s o f t i m e s . T h e r e s u l t s o f t h i s i m a g e e x t r a c t w e r e t h e n p r o c e s s e d into t he

r e a c t i o n r a te d a t a n a m e l y t h e m a s s o f M g O a s a func t ion o f t ime . T h e resu l t o f t he n e x t

p r o c e s s i n g c a n b e d i s p l a y e d in a t a b l e a n d g r a p h i c f o r m s . T h e o b t a i n e d d a t a s e r i e s c a n

a l s o b e e x p o r t e d for p r o c e s s i n g u s i n g a s p r e a d s h e e t p r o g r a m .

T h e s a m p l e o f d a t a p r o c e s s i n g r e s u l t s , i m a g e p i x e l , a n d e s t i m a t e d M g O m a s s , in

t he r e a c t i o n e x p e r i m e n t o f 1.5 m g M g O wi th 2 M H N 0 3 p r o d u c e d f r o m the a p p l i c a t i o n i s

p r e s e n t e d in T a b l e 3 .

T h e s e d a t a w e r e fu r the r p r e s e n t e d a s m a s s of M g O a s a f unc t i on o f t i m e a s s h o w n

in F i g u r e 6 . A s c a n b e s e e n in t h e f i gu re , in bo th the c o n c e n t r a t i o n o f 1 M a n d 2 M of H N 0 3

t he M g O m a s s d e c r e a s e d a s a f u n c t i o n o f t ime . T h e g e n e r a l t r e n d of d e p l e t i o n in s e v e r a l

po in t s m igh t b e d u e to t h e c h a n g i n g pos i t i on o f s o l i d M g O a g a i n s t t h e m i c r o s c o p e pos i t ion .

T h e s h a p e of so l i d M g O w h i c h w a s not fu l l y s p h e r i c a l m a d e it p o s s i b l e for t h i s p h e n o m e n o n

to t a k e p l a c e .

C u r v e fitt ing o f t h e r e s u l t s r e v e a l e d a n e x p o n e n t i a l t r e n d l i ne c u r v e for t he

r e a c t i o n o f 1 M H N 0 3 c o n c e n t r a t i o n , a n d a s e c o n d o r d e r e q u a t i o n for r e a c t i o n d a t a w i t h 2 M

c o n c e n t r a t i o n . E v e n t h o u g h f a c t o r s a f f e c t i n g t h e t r e n d w e r e st i l l u n e x p l a i n a b l e , t h e r e a c t i o n

r a te o f h i g h e r c o n c e n t r a t i o n w a s f a s t e r a s i n d i c a t e d by t he s l o p e . F u r t h e r m o r e , t h e c u r v e s

s h o w the e f f e c t o f c o n c e n t r a t i o n o n r e a c t i o n ra te .

c . I m p l i c a t i o n to c h e m i s t r y l e a r n i n g

T h e o b s e r v a t i o n r e s u l t s o f M g O r e a c t i o n w i t h H N 0 3 c a n b e u s e d to g i v e a n o v e r v i e w

a b o u t so l i d - l i qu id r e a c t i o n s w h i c h a r e r a r e l y u s e d a s e x a m p l e s in c h e m i c a l k i n e t i c s

t e a c h i n g . F u r t h e r m o r e , t he i m a g e of s o l i d M g O a t t he v a r i o u s t i m e i n t e r v a l s c a n b e

p r o c e s s e d into d a t a o n t h e m a s s o f M g O a g a i n s t t i m e for f u r t he r d e v e l o p m e n t o f c h e m i c a l

k i n e t i c s c o n c e p t s , n a m e l y t h e de f in i t i on of r e a c t i o n r a t e s b a s e d o n the M g O m a s s c u r v e

a g a i n s t t i m e . T h e r e a c t i o n v i d e o p r o d u c e d in t h i s s t u d y c a n a l s o b e u s e d to s h o w t h e

i n f l u e n c e of c o n c e n t r a t i o n o n r e a c t i o n r a t e s .

W e n o t i c e d tha t t he qua l i t y o f d a t a o b t a i n e d f r o m th i s e q u i p m e n t s h o u l d b e t r e a t e d

a s e d u c a t i o n a l p u r p o s e s d a t a a n d no t a s a " r e s e a r c h qua l i t y " d a t a . T h e s t u d e n t s s h o u l d b e

r e m i n d e d tha t t h e c a l c u l a t e d m a s s o f t h e s o l i d pa r t i c l e w a s j u s t a n e s t i m a t i o n b a s e d o n the

i m a g e a r e a , a n d not t he a c t u a l m a s s . F u r t h e r m o r e , n o a c c o u n t h a s b e e n t a k e n of c h a n g e s

in s u r f a c e a r e a o f t h e p a r t i c l e . T h e r e f o r e , t h e d a t a , a s u s e d h e r e , c a n o n l y s h o w the

c o n c e p t o f r e a c t i o n r a te a n d a t r e n d t ha t r e a c t i o n r a te i s i n f l u e n c e d b y r e a c t a n t

c o n c e n t r a t i o n . A n e x a m p l e s h o w i n g the l im i ta t ion of t h i s p r o c u d u r e c a n b e s e e n w h e n the

o r d e r o f r e a c t i o n w a s c a l c u l a t e d u s i n g t h e d a t a ; t he o r d e r i s o n e for 1 M H N 0 3 , a n d the

o r d e r i s t w o for 2 M H N 0 3 .

T h e po ten t ia l a d v a n t a g e s of u s i n g t h i s o b s e r v a t i o n a p p a r a t u s for l e a r n i n g c h e m i s t r y a r e

a s f o l l o w s : ( 1 ) t he e x p e r i m e n t a l d a t a o b t a i n e d c a n b e d ig i ta l ly r e c o r d e d a n d r e p l a y e d , ( 2 ) a

l i b ra ry o f e x p e r i m e n t a l d a t a c a n b e r e a d i l y o b t a i n e d , (3 ) t h e c o s t o f t he d ig i ta l m i c r o s c o p e is

l o w a n d ( 4 ) t h e e x p e r i m e n t a l d a t a i s p r o c e s s e d u s i n g a n e a s y to u s e a p p l i c a t i o n to p r o d u c e

k i n e t i c s i n f o rma t i on . T h e d a t a h a s r e l e v a n c e to t he s t u d e n t s b e c a u s e t h e y w a t c h the

r e a c t i o n o c c u r a n d t h e y c a n r e l a t e to t he or ig in o f t he d a t a (it i s not s i m u l a t e d ) . T h e

e x p e r i m e n t h e l p s s t u d e n t s d i r ec t l y l ink t he o b s e r v a b l e ( m a c r o s c o p i c ) p h e n o m e n a w i th t h e

a b s t r a c t ( s u b - m i c r o s c o p i c a n d s y m b o l i c ) t heo re t i ca l c o n c e p t s . T h i s c h e m i c a l r e p r e s e n t a t i o n

c a n b e c o n s i d e r e d a s a s c i e n c e m o d e l i n g s k i l l s a s d e f i n e d by [ 1 3 ] a n d [ 1 4 ] . In add i t i on , a

s m a l l quan t i t y o f c h e m i c a l s i s r e q u i r e d for a n e x p e r i m e n t tha t c a n b e o b s e r v e d b y a l l

s t u d e n t s in t he c l a s s r o o m .

T o s o m e e x t e n t , t h i s r e p o r t e d r e s e a r c h s h o w e d tha t t he e x p e r i m e n t a l p r o c e d u r e

m i m i c k e d the ac t i v i t y o f u s i n g a n " e n v i r o n m e n t a l m i c r o s c o p e " w h e r e a c h e m i c a l r e a c t i o n o r

a p h y s i c a l p r o c e s s e s c a n b e o b e r v e d in-situ. T h i s t y p e of e x p e r i m e n t h e l p s to l ink s c h o o l

c h e m i s t r y w i t h c u r r e n t t e c h n o l o g y a n d / o r c h e m i s t r y r e s e a r c h e x p e r i m e n t s a s r e c o m m e n d e d

by [15 ] a n d s h o w s h o w t e c h n o l o g y c a n b e u s e d a n d d e s i g n e d a l a b e x p e r i m e n t a r e s o u r c e

a s a l s o d o n e b y [ 1 6 ] [ 1 7 ] .

T o e n s u r e tha t t h e d e v e l o p e d a p p r o a c h i s s t r ong l y l e a r n e r f o c c u s e d w e a d a p t e d t h e

A S E L L ( A d v a n c i n g S c i e n c e b y E n h a n c i n g L e a r n i n g in t h e L a b o r a t o r y ) e d u c a t i o n a l a n a l y s i s

( s e e h t t p : / / w w w . a s e l l . o r g / P u b l i c a t i o n s / D o c u m e n t - L i b r a r v ) to d o c u m e n t t h e i n t e n d e d

l e a r n i n g o u t c o m e s . T h i s e d u c a t i o n a l a n a l y s i s i s par t o f a n e d u c a t i o n a l t e m p l a t e f i rst

d e v e l o p e d by B a r r i e a n d c o - w o r k e r s [ 1 8 ] a n d h a s b e e n u s e d , for e x a m p l e , b y o t h e r

7 8

g r o u p [ 1 9 ] . In d o i n g the e x p e r i m e n t , t h e s t u d e n t s w i l l d e v e l o p s c i e n t i f i c a n d p r a c t i c a l s k i l l s

a s d e f i n e d by [ 2 0 ] - [ 2 2 ] , in t h i s c a s e : ( i ) o b s e r v i n g a n d r e c o r d i n g a so l i d - l i qu id r e a c t i o n (ii)

u s i n g i m a g e p r o c e s s i n g s o f t w a r e ( i i i ) t a b u l a t i n g a n d g r a p h i n g d a t a a n d ( i v ) h a n d l i n g o f

a c i d s s a f e l y . T h e y w i l l a l s o d e v e l o p t h i nk i ng a n d g e n e r i c s k i l l s in d a t a a n a l y s i s , c r i t i ca l

t h i nk i ng a n d repo r t w r i t i ng . U l t i m a t e l y , t h e s t u d e n t s wi l l i n c r e a s e the i r t h e o r e t i c a l a n d

c o n c e p t i a l k n o w l e d g e in t he a r e a o f k i n e t i c s a n d r a t e s o f r e a c t i o n s . S p e c i f i c a l l y t h e y wi l l

g a i n a bet te r u n d e r s t a n d i n g t ha t t h e r a t e o f a r e a c t i o n i s a bu l k p rope r t y w h i c h , i n t h i s c a s e ,

r e f e r s to t h e c h a n g e in m a s s o f t h e M g O w i t h r e s p e c t to t i m e . B y c h a n g i n g t h e p a r a m e t e r s

( c o n c e n t r a t i o n o f a c i d , t e m p e r a t u r e a n d o r pa r t i c l e s i z e ) t h e y w i l l a l s o g a i n f i rs t h a n d

e x p e r i e n c e of h o w t h e s e a f f e c t t he r a te o f r e a c t i o n .

F o r t h e p u r p o s e of e d u c a t i o n a l p r a c t i c e s , t he a p p r o a c h m igh t b e e x t e n d e d to o t h e r

p o s s i b l e c h e m i s t r y l e a r n i n g a c t i v i t i e s . O n e o f t h e s e m i g h t b e tha t t h e p r o c e d u r e i s u s e d in

a n inqu i r y s e t t i n g w h e r e t h e s t u d e n t a r e a s k e d to d o a c h e m i c a l k i n e t i c s e x p e r i m e n t in

w h i c h t h e y e x p l o r e t he i m p a c t o f t e m p e r a t u r e , c o n c e n t r a t i o n a n d / o r p a r t i c l e s i z e o n t h e

r e a c t i o n o f M g O wi th H N 0 3 . A n o t h e r o p t i o n m a y b e , i n s t e a d of u s i n g the i m a g e p r o c e s s i n g

s o f t w a r e for a n a l y s i s o f a r e a , t h e s t u d e n t s c a n f ind the m a s s o f M g O b y cu t t i ng t h e p r i n ted

i m a g e , w e i g h i n g the p a p e r f o l l o w e d b y c a l c u l a t i n g t he M g O m a s s . A v a r i e t y a r e s u l t s wi l l b e

o b t a i n e d f r o m e v e r y s t u d e n t , t h u s i n t r o d u c i n g the c o n c e p t o f s a m p l i n g a n d m e a s u r e m e n t

u n c e r t a i n t y . O t h e r a p p l i c a t i o n s w h i c h m a y b e u s e d c o u l d i n c l u d e t h e d i s s o l u t i o n p r o c e s s o f

s o l u b l e s o l i d s , p rec i p i t a t i on a n d c r y s t a l g r o w t h .

C o n c l u s i o n

A d ig i ta l m i c r o s c o p e i s a s i m p l e p i e c e of l a b e q u i p m e n t t ha t c a n b e u s e d to to v i d e o

r e c o r d a n d d e m o n s t r a t e t h e r a t e o f n o n - g a s p r o d u c i n g so l i d - l i qu id r e a c t i o n s s u c h a s

m a g n e s i u m o x i d e a n d ni t r ic a c i d . T h e v i d e o p r o c e s s i n g a p p l i c a t i o n ( a v a i l a b l e f r o m t h e

c o r r e s p o n d i n g a u t h o r ) for c h e m i c a l o b s e r v a t i o n d e v e l o p e d in th is s t u d y i s a b l e to e x t r a c t

i m a g e s of so l i d M g O a t s e v e r a l t i m e i n t e r v a l s that c a n fu r ther b e u s e d to e x p l a i n t he

c o n c e p t s , de f in i t ion o f r e a c t i o n r a t e s , a n d the i n f l u e n c e of c o n c e n t r a t i o n o n c h e m i c a l

r e a c t i o n r a t e s . T h e p r o c e d u r e h a s t h e po ten t ia l to b e u s e d in a n inqu i ry l e a r n i n g se t t i ng to

e x p l o r e s t u d e n t s ' c r e a t i v e t h i n k i n g .

H a z a r d a n d s a f e t y

W h e n a p p l y i n g th is e x p e r i m e n t : a v o i d e y e a n d s k i n c o n t a c t w i th H N 0 3 a n d H C I . C o n t a c t

w i t h t h e l i qu ids i s c o r r o s i v e to t he e y e s a n d c a u s e s s e v e r e b u r n s . I n g e s t i o n w i th t he

s u b s t a n c e m a y c a u s e c i r c u l a t o r y s y s t e m fa i l u re . C a u s e s s e v e r e d i g e s t i v e t rac t b u r n s w i t h

a b d o m i n a l p a i n , v o m i t i n g , a n d p o s s i b l e d e a t h .

A c k n o w l e d g e m e n t

T h e o u t h o r s w o u l d l i ke to t h a n k :

U P I f o r f i n a n c i a l s u p p o r t t o t h i s r e s e a c h p r o j e c t a n d f o r f i n a n c i n g t h e s h o r t v i s i t i n g

r e s e a r c h p r o g r a m to C h e m i s t r y D e p a r t e m e n t , C u r t i n U n i v e r s i t y A u s t r a l i a

M r . D e n i P u r n a m a ; U P I I n f o r m a t i o n T e h n o l o g y a n d C o m m u n i c a t i o n s t a f , t h a t k i n d l y

bu i l t t h e a p p l i c a t i o n u s e d in t h i s r e s e a r c h

R E F E R E N C E

[1 ] X . S . F a n g , C . H . Y e , L. D. Z h a n g , J . X . Z h a n g , Z . W . Z h a o , a n d P . Y a n , " D i r e c t

O b s e r v a t i o n o f t h e G r o w t h P r o c e s s o f M g O N a n o f l o w e r s b y a S i m p l e C h e m i c a l

9 Hi

R o u t e , " Small, v o l . 1 , n o . 4 , pp . 4 2 2 - 4 2 8 , 2 0 0 5 .

[2] A . S e t i a b u d i , N. K . A l l a a r t , M . M a k k e e , a n d J . a . Mou l i j n , " I n s i t u v i s i b l e m i c r o s c o p i c

s t u d y o f m o l t e n C s 2 S 0 4 V 2 0 5 - s o o t s y s t e m : P h y s i c a l i n t e r a c t i o n , o x i d a t i o n r a t e , a n d

d a t a e v a l u a t i o n , " Appl. Catal. B Environ., v o l . 6 0 , pp. 2 3 3 - 2 4 3 , 2 0 0 5 .

[3 ] J . C a r n d u f f , " D i r e c t o b s e r v a t i o n o f c h e m i c a l r e a c t i o n s o n s i n g l e g o l d n a n o c r y s t a l s

u s i n g s u r f a c e p l a s m o n s p e c t r o s c o p y , " Nat. Nanotechnol., v o l . 3 , n o . 1 0 , pp . 5 9 8 -

6 0 2 , 2 0 0 8 .

[4 ] M. A . L e m a , E . M. A l j i n o v i c , a n d M. E . L o z a n o , " U s i n g a h o m e m a d e

s p e c t r o p h o t o m e t e r in t e a c h i n g b i o s c i e n c e s , " Biochem. Mol. Biol. Educ, v o l . 3 0 , no .

2 , pp . 1 0 6 - 1 1 0 , 2 0 0 2 .

[ 5 ] J . Q u a g l i a n o a n d C . M a r k s , " D e m y s t i f y i n g S p e c t r o s c o p y w i th S e c o n d a r y S t u d e n t s :

D e s i g n i n g a n d U s i n g a C u s t o m - B u i l t S p e c t r o m e t e r , " J. Chem. Educ, v o l . 9 0 , pp.

1 4 0 9 - 1 4 1 0 , 2 0 1 3 .

[ 6 ] T . A u n g a n d C . A . L i b e r k o , " B r i n g i n g P h o t o c h e m i s t r y to t he M a s s e s : A S i m p l e , E ff

e c t i v e , a n d I n e x p e n s i v e P h o t o r e a c t o r , R i g h t O u t o f t h e B o x , " n o . F i g u r e 1 , pp. 8 - 1 1 ,

2 0 1 4 .

[7 ] M . L . H a m a d , " M e a s u r i n g T a b l e t D i s s o l u t i o n : A n E x p e r i m e n t for T e a c h i n g

Q u a n t i t a t i v e U l t r a v i o l e t A b s o r p t i o n S p e c t r o s c o p y , " pp. 1 6 6 2 - 1 6 6 4 , 2 0 1 3 .

[8 ] C . A . C l o o n a n , C . A . N i c h o l , a n d J . S . H u t c h i n s o n , " U n d e r s t a n d i n g C h e m i c a l

R e a c t i o n K i n e t i c s a n d E q u i l i b r i u m w i t h I n t e r l ock i ng B u i l d i n g B l o c k s , " v o l . c , pp .

1 4 0 0 - 1 4 0 3 , 2 0 1 1 .

[9 ] C . J . F e n k a n d N. K a u f m a n , " A N e w C o l o r i m e t r i c A s s a y of T a b l e t o p S w e e t e n e r s

U s i n g a Mod i f i ed B i u r e t R e a g e n t A n A n a l y t i c a l C h e m i s t r y E x p e r i m e n t for t h e

U n d e r g r a d u a t e C u r r i c u l u m W , " v o l . 8 4 , n o . 1 0 , 2 0 0 7 .

I I

[ 1 0 ] S . C . M a r v e l a n d M. V K e p l e r , " I N Q U I R Y & A S i m p l e M e m b r a n e O s m o m e t e r

I N V E S T I G A T I O N S y s t e m & E x p e r i m e n t s T h a t Q u a n t i t a t i v e l y M e a s u r e O s m o t i c

P r e s s u r e , " v o l . 7 1 , n o . 6 , pp . 3 5 5 - 3 6 2 , 2 0 1 5 .

[ 1 1 ] A . S e t i a b u d i , G . Y u l i a n i , a n d Z . P a w i t a n , " A n o x y g e n s e n s o r u s i n g z i n c - a i r

e l e c t r o c h e m i c a l c e l l s : a s i m p l e d e v i c e to d e m o n s t r a t e a p p l i e d t e c h n o l o g y in

e l e c t r o c h e m i s t r y t e a c h i n g , " v o l . 9 7 , n o . 3 6 1 , pp . 3 3 - 3 7 , 2 0 1 6 .

[ 1 2 ] T . A u n g a n d C . a . L i b e r k o , " B r i n g i n g p h o t o c h e m i s t r y to t h e m a s s e s : A s i m p l e ,

e f f e c t i v e , a n d i n e x p e n s i v e p h o t o r e a c t o r , r ight ou t o f t he b o x , " J. Chem. Educ, v o l .

9 1 , n o . 6 , pp . 9 3 9 - 9 4 2 , 2 0 1 4 .

[13 ] G . C h i t t l e b o r o u g h a n d D. F . T r e a g u s t , " T h e m o d e l l i n g abi l i ty o f n o n - m a j o r c h e m i s t r y

s t u d e n t s a n d the i r u n d e r s t a n d i n g of t h e s u b - m i c r o s c o p i c l e v e l , " v o l . 8 , n o . 3 , pp.

2 7 4 - 2 9 2 , 2 0 0 7 .

[ 1 4 ] J . K . G i l b e r t , " T h e r o l e o f v i s u a l r e p r e s e n t a t i o n s in t he l e a r n i n g a n d t e a c h i n g o f

s c i e n c e : A n in t roduc t ion , " in Asia-Pacific Forum on Science Learning and Teaching,

2 0 1 0 , v o l . 1 1 , no . 1 , pp. 1 - 1 9 .

[ 1 5 ] A m e r i c a n C h e m i c a l S o c i e t y , ACS Guidelines and Recom m endations for the

Teaching of High School Chemistry. A C S , 2 0 1 2 .

[ 1 6 ] A . K l u g e , " C o m b i n i n g L a b o r a t o r y E x p e r i m e n t s w i t h D ig i ta l T o o l s to D o S c i e n t i f i c

Inqu i ry C o m b i n i n g L a b o r a t o r y E x p e r i m e n t s w i th D ig i ta l T o o l s to D o S c i e n t i f i c

Inqu i ry , " v o l . 0 6 9 3 , no . D e c e m b e r , 2 0 1 5 .

[ 1 7 ] S . S . G u z e y a n d G . H . R o e h r i g , " T e a c h i n g S c i e n c e w i th T e c h n o l o g y : C a s e S t u d i e s

o f S c i e n c e T e a c h e r s ' D e v e l o p m e n t of T e c h n o l o g y , P e d a g o g y , a n d C o n t e n t

K n o w l e d g e , " . Contemp. Issues Technol. Teach. Educ, v o l . 9 , n o . 1 , pp . 2 5 - 4 5 ,

2 0 0 9 .

i :

[ 1 8 ] S . C . B a r r i e , M. A . B u n t i n e , M . J a m i e , a n d S . H . K a b l e , " A P C E L L : T h e A u s t r a l i a n

P h y s i c a l C h e m i s t r y E n h a n c e d L a b o r a t o r y L e a r n i n g P r o j e c t , " Aust. J. Educ. Chem.,

v o l . 5 7 , n o . -, p. 6 , 2 0 0 1 .

[ 1 9 ] K . F . L i m , " A n I R i n v e s t i g a t i o n o f t he C O d i p o l e d i r ec t i on a n d o t h e r p r o p e r t i e s : A n

A P C E L L e x p e r i m e n t l , " Aust. J. Educ. Chem., v o l . 5 4 , p. 2 4 , 2 0 0 4 .

[ 2 0 ] R . B l o n d e r , R . M a m l o c k - N a a m a n , a n d A . H o f s t e i n , " A n a l y z i n g inqu i r y q u e s t i o n s o f

h i g h - s c h o o l s t u d e n t s in a g a s c h r o m a t o g r a p h y o p e n - e n d e d l a b o r a t o r y e x p e r i m e n t , "

Chem. Educ. Res. Pract, v o l . 9 , n o . 3 , pp . 2 5 0 - 2 5 8 , 2 0 0 8 .

[21 ] C . J . S m i t h , " I m p r o v i n g the s c h o o l - t o - u n i v e r s i t y t r a n s i t i o n : u s i n g a p r o b l e m - b a s e d

a p p r o a c h to t e a c h p r a c t i c a l s k i l l s w h i l s t s i m u l t a n e o u s l y d e v e l o p i n g s t u d e n t s '

i n d e p e n d e n t s t u d y s k i l l s , " Chem. Educ. Res. Pract, v o l . 1 3 , n o . 4 , p. 4 9 0 , 2 0 1 2 .

[ 2 2 ] A . H o f s t e i n a n d R . M a m l o k - N a a m a n , " T h e l a b o r a t o r y i n s c i e n c e e d u c a t i o n : t h e s t a t e

o f t he a r t , " Chem. Educ. Res. Pract, v o l . 8 , n o . 2 , p. 1 0 5 , 2 0 0 7 .

13

L i s t o f T a b l e s

T a b l e 1 . S u m m a r y o f so l i d - l i qu id r e a c t i o n o b s e r v a t i o n t e s t

T a b l e 2 T h e s c r e e n s h o t s o f t h e o b s e r v a t i o n r e s u l t s : t he reac t i on o f s o l i d M g O

T a b l e 3 . E x a m p l e s o f d a t a p r o c e s s i n g r e s u l t o f so l id - l iqu id r e a c t i o n o b s e r v a t i o n app l i ca t i on

T a b l e 1 . S u m m a r y o f so l i d - l i qu id r e a c t i o n o b s e r v a t i o n t e s t

N o R e a c t i o n N o t e s o n t h e v i d e o r e c o r d i n g

1 . Z n + H C I • T h e p a r t i c l e i m a g e w a s di f f icul t to a n a l y s e d u e to t h e

p o s i t i o n c h a n g e s .

• T h e so l i d p l a t e e d g e s w i t h t h e b u b b l e s i s not c l e a r

• T w o - d i m e n s i o n a l s h a p e o f s o l i d z i n c ( p l a t e ) d id not

r e p r e s e n t t he z i n c quan t i t y

• T h e s i z e took a l ong t i m e to c h a n g e

2 . F e + H C I • T h e pa r t i c l e i m a g e w a s d i f f icu l t to a n a l y s e d u e to pos i t i on

c h a n g e a n d the c o l o r o f F e i m a g e w h i c h r e s e m b l e d t h e

i m a g e of g a s b u b b l e s

• T h e i ron g r a i n m o v e d f r o m i ts pos i t i on for s e v e r a l t i m e s

d u e to t h e h i g h g a s p r o d u c t i o n

• T h e s i z e took a l ong t i m e to c h a n g e

• T h e p a r t i c l e o f C a C 0 3 sp l i t in to s e v e r a l p a r t s r e s u l t i n q in 3 . C a C 0 3 + H C I

d i f f icul ty in a n a l y s i n g t h e i m a g e - d u e to t he s i z e

4 . M g O + H N 0 3 • T h e c o l o r o f M g O s o l i d w a s r e l a t i v e l y in c o n t r a s t w i t h

t ha t o f t he v e r y little b u b b l e s tha t c o u l d st i l l b e

o b s e r v e d

• T h e M g O g r a i n w a s r e l a t i v e l y i n tac t s o t ha t t h e s i z e o f t h e

r e m a i n i n g M g O c o u l d b e a n a l y s e d .

• C h a n g e s in s i z e took p l a c e w i t h i n a r e a s o n a b l e t i m e

i n t e r v a l

15

T a b l e 2 T h e s c r e e n s h o t s o f t h e o b s e r v a t i o n r e s u l t s : t h e r e a c t i o n of so l i d M g O

T i m e ( s ) M g O I m a g e R e m a r k s

B e f o r e r e a c t i o n

l i i i i l i in

T h e i m a g e of a n M g O g r a i n be fo re r e a c t i o n .

T h e g ra i n w a s a r o u n d 2 m m in s i z e a n d 1.5 m g in

CO

1 2 0

T h e i m a g e of t he M g O g ra i n s o o n a f te r t he add inc

n i t r ic a c i d so lu t i on

T h e i m a g e of M g O g ra i n a t 6 0 , 1 2 0 , a n d 2 4 0 s a f

add i t i on o f n i t r ic a c i d so lu t i on . T h e pa r t i c le s i z e de

c o m p a r e d to t he in i t ia l .

16

Table 3. Examples of data processing result of solid-liquid reaction observation

application

R e a c t i o n t i m e ( s e c o n d )

M g O i m a g e ( P i x e l )

M g O m a s s e s t i m a t e d ( m g )

0 8 1 5 1 1.50

3 0 7 6 5 7 1 4 1

1 0 0 5 2 8 5 0 . 8 4

2 0 0 1 6 8 8 0 . 3 1

1 7

L i s t o f F i g u r e s

F i g u r e 1 . L o g i c a l f r a m e w o r k for t h e d e v e l o p m e n t o f t h i s s i m p l e e q u i p m e n t

F i g u r e 2 . S c h e m a t i c a r r a n g e m e n t of t he so l id - l iqu id c h e m i c a l r e a c t i o n o b s e r v a t i o n k i t s

F i g u r e 3 . A p p l i c a t i o n w o r k f l o w to p r o c e s t h e v i d e o of c h e m i c a l r e a c t i o n in to c h e m i c a l

k i n e t i c s ( m a s s v s . t i m e ) d a t a

F i g u r e 4 . T h e s c r e e n s h o t s o f t he r e a c t i o n v i d e o b e t w e e n : a ) z i n c a n d h y d r o c h l o r i c a c i d , b )

i ron a n d h y d r o c h l o r i c a c i d , a n d ( c ) c a l c i u m c a r b o n a t e a n d h y d r o c h l o r i c a c i d

F i g u r e 5 . T h e a p p l i c a t i o n s c r e e n s h o t d i s p l a y i n g a v i d e o i m a g e b e i n g p l a y e d

F i g u r e 6 . P l o t o f M g O m a s s a g a i n s t r e a c t i o n t i m e o b s e r v e d u s i n g a m i c r o s c o p e a n d

p r o c e s s e d u s i n g the a p p l i c a t i o n w i th d i f fe ren t c o n c e n t r a t i o n o f H N 0 3 .

i s

Microscopically Snap-shated at a observed and series of time

recorded

Image processing

Image area and mass calculation

Used to determine rate of reoction

F i g u r e 1 . L o g i c a l f r a m e w o r k for t he d e v e l o p m e n t o f t h i s s i m p l e e q u i p m e n t

Digital microscope

Petri disc (chemical reactor)

Computer

F i g u r e 2 . S c h e m a t i c a r r a n g e m e n t of t he so l id - l iqu id c h e m i c a l r e a c t i o n o b s e r v a t i o n k i t s

19 20

F i g u r e 5 . T h e a p p l i c a t i o n s c r e e n s h o t d i s p l a y i n g a v i d e o i m a g e b e i n g p l a y e d

2 3

11

0 100 200 300 400 MO 000 700 r ime (second)

F i g u r e 6 . P lo t o f M g O m a s s a g a i n s t r e a c t i o n t i m e o b s e r v e d u s i n g a m i c r o s c o p e a n d

p r o c e s s e d u s i n g the a p p l i c a t i o n w i t h d i f fe ren t c o n c e n t r a t i o n o f H N 0 3 .

24