acids and bases roselyn dooley, tyler schmidt, kyle doubleday and deondré robinson

Acids and BasesRoselyn Dooley, Tyler Schmidt, Kyle Doubleday and Deondré Robinson

Properties of Acids

-Sour taste

-React with active metals

-Turns litmus paper Red

-React with bases to produce salt and water

-Conduct electricity

-1- 6.9 on pH scale

Properties of Bases

-Bitter taste

-Slippery feel

-Turns litmus paper blue

-Reacts with acids to produce salt and water

-Conduct electricity

-7.1 - 14 on pH scale

Binary and Tertiary acids

Binary acid- an acid that contains only two different elements: hydrogen and one of the more electronegative elements.

Tertiary acid- an acid that contains hydrogen oxygen and one more element.

Theories of Acids and Bases

-Arrhenius

Acid- A substance that dissociates to produce hydrogen ions in water

Base- A substance that dissociates to produce hydroxide ions in water

-Bronsted-Lowry

Acid- Any substance that can donate H+ ions. (A proton donor)

Base- Any substance that can accept H+ ions. (A proton acceptor)

Theories of Acids and Bases Cont.

-Lewis

Acid- Any substance that can accept a pair of nonbonding electrons. (electron pair acceptor)

Base- Any substance that can donate a pair of nonbonding electrons. (electron pair donor)

Naming Acids

• Rule #1o If the negative ion in the acid ends in "ide" you name

the acid "Hyrdo (stem) ic acid Ex: HCl (Chloride) would yield Hydrochloric acid

• Rule # 2o If the negative ion in the acid ends in "ite", you name

the acid "(stem)ous acid" Ex: HNO2 (Nitrite) would yield Nitrous Acid

*Use only if there is an oxygen in the chemical formula

Naming Acids Cont.

• Rule # 3o If the negative ion ends in "ate", you name the acid

"(stem)ic" acid. Ex: HIO4 (Periodate) would yield Periodic acid Note: The stem of Sulfur is Sulfur

• Also the Stem of Phosphor is phosphor

Name that Acid!

1. HSCN

2. HClO2

3. HClO3

4. HBr

5. H2SO3

6. H3P

Answers

1. Thiocyanic acid

2. Chlorous acid

3. Chloric acid

4. Hydrobromic acid

5. Sulfurous acid

6. Hydrophosphoric acis

pH Scale

Six Strong Acids

• HCl

• HBr

• HI

• HNO3

• H2SO4

• HClO4

o Everything else is considered a weak acid

Writing Acid-base reactions in aqueous solutions

General Formulas

Strong Acids Weak Acids

HA H+1 + A-1

HCl H+1 + Cl-1

HA +H2O H3O+1 +A-1

HF + H2O H3O+1 + F-1

Now you try

1. HBr2. H2SO4

3. HCN4. HC2H3O2

Write the acid base reactions in aqueous solutions

Answers

1. HBr H+1 + Br-1

2. H2SO4 H+1 + SO4-2

3. HCN + H2O H3O+1 + CN-1

4. HC2H3O2 + H2O H3O+1 + C2H3O2-1

Neutralization Reactions between Acids and Bases

Neutralization- The reaction of hydronium ions and hydroxide ions to form water molecules

Example equation-

HCl(aq) + NaOH(aq) NaCl(aq)+ H2O(l)

Note: This is basically just a double displacement reaction

Now you try

1. HClO4(aq)+ NaOH(aq)

2. HBr(aq) + Ba(OH)2 (aq)

***You might need your pink sheet

Answers

1. HClO4(aq)+ NaOH(aq) NaClO4(aq)+ H2O(l)

2. 2HBr (aq)+ Ba(OH)2 (aq) BaBr2 (aq) +

2H2O(l)

Calculate Hydronium and Hydroxide

[H+]=10-pH

ex. [H+]=10-4

[H+]=1 x 10-4 M

1. pH= 2.2

2. pH=3.6

3. pH=8.8

4. pOH=9

[OH-]=10-pOH

ex. [OH-]=10-7.5

[OH-]=3.16 x 10-8 M

1. pOH=7.8

2. pOH=9.3

3. pOH=5.6

4. pH=3

Hydronium and Hydroxide Answers

1. [H+]= .0063 M

2. [H+]= 2.51 x 10-4 M

3. [H+]= 1.58 x 10-9 M

4. [H+]= 1 x 10-9 M

1. [OH-]= 1.58 x 10-8 M

2. [OH-]= 5.01 x 10-10 M

3. [OH-]= 2.51 x 10-6 M

4. [OH-]= .001 M

Calculate pH and pOHpH=-log[H+]

ex. pH=-log[2.33 x 10-9 M]

pH=8.63

1. [H+]=7.24 x 10-5 M

2. [H+]=6.32 x 10-2 M

3. [OH-]=2.26 x 10-8 M

4. [H+]=4.54 x 10-3 M

pOH=-log[OH-]

ex. pOH=-log[7.65 x 10-3 M]

pOH=2.12

1. [OH-]=5.58 x 10-4 M

2. [OH-]=3.67 x 10-8 M

3. [OH-]=2.77 x 10-2 M

4. [H+]=4.49 x 10-7 M

pH and pOH Answers

1. pH= 4.14

2. pH= 1.2

3. pH= 6.35

4. pH= 2.34

1. pOH= 3.25

2. pOH= 7.43

3. pOH= 1.56

4. pOH= 7.65

Titration

The controlled addition and measurement of the amount of a solution of known concentration required to react completely with a measured amount of a solution of unknown concentration.

Once the two solutions are chemically equivalent, the solution has reached the equivalence point.

Titration

Essentially, you add an acid of known molarity (concentration) to a base of unknown molarity in measured amounts to find the unknown, or vice versa.

Once at the equivalence point, the unknown concentration can be calculated using known concentration and volumes.

Walkthrough Problem

500 mL of .5 M HF titrates with 635 mL NaOH.

1) Balance the equation:

HF + NaOH NaF + H2O

2) Choose method: M1V1 = M2V2 or conversions

3) (.5M) (.500 L) = (x M) (.635 L)

4) .5 M (.500 L)

.635 L

5) .4 M NaOH

Titration Calculations

Ex 1) 25 mL of .3M HCl reaches an equivalence point with 75 mL of NaOH. What is the molarity of the NaOH?

Titration Calculations

1) Balance the equation:

HCl + NaOH NaCl + H2O

2) Because the mole ratios are equal (1:1), we can use the formula M1V1 = M2V2

3) (.3M) (.025 L) = (x M) (.075 L)

4) .3 M (.025 L)

.075 L

5) .1 M NaOH

= x M

Titration Calculations

Ex 2) 550 mL of H2SO4 of unknown concentration reaches an equivalence point with 775 mL of 2.0 M NaOH. What is the concentration of the H2SO4.

Titration Calculations

1) Balance the equation:

H2SO4 + 2NaOH Na2SO4 + 2H2O

2) Because the mole ratios are not equal (1:2), we must use conversion factors.

3) 2.0 M NaOH = (x) mols NaOH

.775 L NaOH

4) 1.55 mols NaOH x 1 mol H2SO4 = .755 mols H2SO4

2 mols NaOH

5) .755 mols H2SO4 = 1.4 M H2SO4

.550 L H2SO4

Questions for us

Sourceshttp://www.google.com/imgres?imgurl=http://www.dartmouth.edu/~chemlab/techniques/graphics/titration/titration10.gif&imgrefurl=http://www.dartmouth.edu/~chemlab/techniques/titration.html&h=263&w=190&sz=32&tbnid=ZR_ZcE0XRTe1TM:&tbnh=90&tbnw=65&zoom=1&usg=__Lx_UdDHNNq5SJQMUUATJ_Hg7nCc=&docid=8iiaXS9UV6QRhM&sa=X&ei=gF6tUfDeDtCJ0QHFg4DgCA&sqi=2&ved=0CF4Q9QEwBg&dur=155

http://www.elmhurst.edu/~chm/vchembook/184ph.html

http://copernicusconsulting.net/designers-are-not-researchers-the-difference-between-design-and-social-research/

http://www.thechemicalblog.co.uk/what-is-a-titration/

http://dl.clackamas.edu/ch104-04/double.htm

http://www.pc.maricopa.edu/data/GlobalFiles/file/chemistry/lee/Double%20displacement%20reaction.pdf

https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&docid=bZiz86EUg2v9FM&tbnid=h7bsJowJO9PdSM:&ved=0CAUQjRw&url=http%3A%2F%2Fthepickledhedgehog.com%2F2012%2F02%2F21%2Fscience-life%2F&ei=Rl-tUYjpM8aw0AGWpoCQAw&bvm=bv.47244034,d.dmQ&psig=AFQjCNH5PX-KRxbEbTHb1ihQtytljDNj1Q&ust=1370403008833830