When we think of acids and bases we tend to think of chemistry lab acids and bases likeBut we are surrounded by acids and bases in the world. Most of them are weak.Acids cause:

| Lemons to be sour

| Acid rain to eat away at sculptures

| Cavities in your teeth

| Digestion of food in your stomach

| Ants to give you a nasty bite

Properties of an Acid| Tastes sour| Turns litmus paper red| Has a pH of less than 7| Lemon juice and vinegar are acids

Properties of a Base| Taste bitter and have a slippery feel| Turns litmus paper blue| Has a pH greater than 7| Bases that are soluble (dissolve in water)

are called alkalis| Most hand soaps and drain cleaners are bases

| Hydrochloric acid, HCl and sulfuric acid H2SO4 are very corrosive

| Carbonic acid is used in fizzy drinks| Ethanoic acid is in vinegar| Citric acid is in oranges and lemons

| Sodium hydroxide, NaOH is very corrosive and is known as caustic soda

| Calcium hydroxide Ca(OH)2 forms limewater when dissolved in water

Tea contains tannic acid

Carbonated soft drinks contain carbonic acid

Fruit contains citric acid

Strenuous exercise causes a buildup of lactic acid in muscle tissue

Acid rain (nitric /sulfuric acid) corroding a limestone sculpture.

Acid rain kills trees and aquatic life

H2SO4pH = 1

turns red

Lemon juicepH = 3

turns orange

RainwaterpH = 6

turns yellow

Window cleanerpH = 10

turns blue

NaOHpH = 14

turns navy

The pH scale is a way of expressing the strength of acids and bases

The pH scale goes from 0 to 14

Under 7 = acid7 = neutral

Over 7 = base

| These are chemicals that change colour in the presence of an acid or a base.

| There are a number of different indicators that change color at different pH’s.

HCl + NaOH → NaCl + H2O

| Acids and alkalis react together to form a neutral salt and water

| A salt is formed when a metal ion replaces the hydrogen in an acid

Cl + OHH Na

OC38Burette

Retort stand

Conical flask

Hydrochloric acid

Sodium hydroxide and litmus

indicator solution

2HCl + CaCO3 → CaCl2 + H2O + CO2

Acid + Carbonate → Salt + Water + Carbon Dioxide