Acid and Base

Mattayomsuksa 4

Chemistry

vocabulary

arrhenius

aqueous

solution

slippery

neutral

structure

Comparative sentence

We use the comparative to compare and contrast different objects.

One-syllable adjectives : Adj adding – er : low-lower, cool - cooler, tall – taller, warm – warmer, etc. For example

- Lower pH value indicates a stronger acid. - Higher pH value indicates a stronger base.

Acid and Base

Arrhenius Acids and Bases

Acids produce H+ in aqueous solutions water

HCl H+(aq) + Cl- (aq))

Bases produce OH- in aqueous solutions water

NaOH Na+(aq) + OH- (aq)

Acids

þ Produce H+ (as H3O+) ions in water

þ Produce a negative ion (-) too

þ Taste sour

þ Corrode metals

þ React with bases to form salts and water

þNeutral Substance : Water!

Bases

Produce OH- ions in water

Taste bitter, chalky

Are electrolytes

Feel soapy, slippery

React with acids to form salts and water

Neutral Substance : Water!

What is the pH scale?

• Acids have a ph from 0-7• Lower pH value indicates a

stronger acid.

• Bases have a pH from 7-14• Higher pH value indicates a

stronger base.

Some Common Acids

NaOH sodium hydroxide (found in soap)

HCl hydrochloric acid NaHCo3 sodium bicarbonate acidHNO3 nitric acid

(found in sanitary ware cleaner)

What produce a negative ions ?

A PH from 0-7 is Acid or Base ?

What neutral substance ?

Listening quiz game

1 2 3

4 5

NaOH , Base

HCL , Acid

Washing up , Base

HNO3 , Acid

NaHCo3 , Base

Acids and Base laboratory

instruction

You have to do experiment of Acids and Base then write down transference and result of lab. After that you have to present lab result in front of the class.

- Drop blue- pea juice 5 drops in lemon juice, orange juice, soap liquid, and detergent .- Observe transference of lab.- Write down the result of lab.

How to do the experiment

LAB resultSolution Transferenc

e Result ( acid or base)

Lemon juice+ blue- pea juiceSoap liquid+ blue- pea juiceOrange juice+ blue pea juiceDetergent+ blue pea juice

Summary of experiment………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………