LO1 Lesson 12 Chemistry Quiz

What colour does blue litmus paper turn when exposed to an acid?

• green

• orange

• red

• yellow

Answer explanation

Blue litmus paper turns red when exposed to an acid, indicating acidity.

pH7.1 to pH14 is the value of:

• acid

• alkaline

• hydrogen

• neutral

Answer explanation

pH7.1 to pH14 is alkaline because it falls within the range of basic or alkaline substances on the pH scale.

Which of these pH values would be considered the strongest alkali?

• pH11

• pH12

• pH13

• pH14

Answer explanation

pH14 is the strongest alkali as it has the highest pH value, indicating a high concentration of hydroxide ions.

Which pH value shows neutral?

• pH5

• pH7

• pH9

• pH11

Answer explanation

pH7 is considered neutral because it is neither acidic nor basic, making it the correct choice.

Which of these pH values would be classed as strong acid?

• pH3

• pH6

• pH9

• pH12

Answer explanation

A pH value of 3 is considered a strong acid due to its low value on the pH scale, indicating high acidity.

Outline one benefit of using acid balanced products on the hair:

• Cuticles are smooth and closed

• Hair will tangle less

• Hair will look shiny

• Hair will not become dry and brittle

Answer explanation

Using acid balanced products on the hair helps to keep the cuticles smooth and closed, resulting in healthier and shinier hair.

Outline the purpose of litmus paper:

• Litmus paper is used to test the pH balance of a water-based product

• It will only tell you if the substance is acidic or alkaline, not the strength of the pH

Answer explanation

Litmus paper is used to test the pH balance of a water-based product.

Outline what happens when acids and alkalis are brought together?

Answer explanation

When acids and alkalis are brought together, they neutralize each other, forming water and a salt. This reaction is called neutralization.

Identify the impact on the hair structure if a product with high acid pH is used?

Answer explanation

Using a product with high acid pH can cause damage to the hair structure by weakening the hair shaft and disrupting the natural pH balance of the scalp.

Outline how pH balanced products support the skin structure?

Answer explanation

pH balanced products help maintain the skin's natural acidity, preventing disruption to the skin barrier and supporting the skin structure.