Do now!

Can you spell the following words

correctly in the back of your book?

Nuetralisasion, indicater, litmas, alkcali, burete.

Acids and alkalis

What have you learnt?

Acid tastes

Acid tastes

Acid comes from the latin word acer, which means sharp. Acids are sharp tasting! (“Tangy”)

Indicators

Indicators are chemicals (coloured dyes) which change colour in acids and alkalis.

Litmus

Turns red in acid

Turns blue in alkali

Litmus

Turns red in acid

Turns blue in alkali

Litmus can tell us if something is an acid or an alkali, but it cannot tell us how strong the

acid or alkali is

Other indicators

Red cabbage and beetroot make excellent indicators

The pH scale

The strength of an acid is measured on the pH scale

pH stands for the “potential of hydrogen”

Universal Indicator

To measure pH, we need an indicator that has a different colour for each value of pH

Universal Indicator

Universal Indicator

It comes in the form of a paper

Universal Indicator

It also comes in the form of a liquid

Neutralisation

Neutralisation

What happens when we add an acid to an alkali?

Neutralisation

Acid + alkali salt + water

Both neutral

Examples of neutralisation

Chemical Hazard Symbols

• Corrosive – dissolves metals, stone and skin

• Irritant – harms eyes and skin

• Flammable – burns easily

• Toxic – poisonous

Summary sheet

Can you stick the summary sheet into your books?

Summary exercise

Read pages 64 and 65

Abigail Tom

Read pages 64 and 65

Abigail Tom

Can you now write 6 multiple choice questions to go with these pages

Multiple choice questions

What is a burette used for?

Multiple choice questions

What is a burette used for?

A. to add measured amounts of a liquid

Multiple choice questions

What is a burette used for?

A. to add measured amounts of a liquid

B. to stir reactants together

Multiple choice questions

What is a burette used for?

A. to add measured amounts of a liquid

B. to stir reactants together

C. to grind solids into a powder

Multiple choice questions

What is a burette used for?

A. to add measured amounts of a liquid

B. to stir reactants together

C. to grind solids into a powder

D. to make french toast

Read pages 64 and 65

Abigail Tom

Can you now write 6 multiple choice questions to go with these pages

TEST

We will be having an acids and alkalis TEST on Monday 17th December