Acids and bases

This task is about reading and using a pH scale.
The pH scale measures how acidic or basic a substance is. Five solutions, shown as A, B, C, D and E, are shown on the pH scale below.
labelled ph scale
Solution A is lemon juice.
Solution B is coffee.
Solution C is pure water.
Solution D is baking soda.
Solution E is oven cleaner.

Question 1Change answer

What is the pH of coffee? 

What is the pH of baking soda? 

What is the pH of oven cleaner? 

Question

Chemists say that an acid and a base cancel or neutralise each other.
Which of the following substances would a gardener use to make a soil of pH 5.5 suitable for a plant that grows best in slightly basic soil?

    • Caustic soda (pH 13)

    • Water (pH 7)

    • Chicken manure (pH 9)

    • Citrus peel (pH 6.5)

Question

Choose whether the following statement is true or false: 
Solution E is more acidic than Solution B.

    • true

    • false

Question

Choose whether the following statement is true or false: 
Solution E is more basic than Solution D.

    • true

    • false

Question

Choose whether the following statement is true or false: 
Solution C is neutral.

    • true

    • false

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