Strong and Weak Acids AQA GCSE

Which of the following is the correct definition for a strong acid?

• Partially dissociates into ions when dissolved in water and the change is not reversible

• Fully dissociates into ions when dissolved in water and the change is not reversible

• Fully dissociates into ions when dissolved in water and the change is reversible

• Partially dissociates into ions when dissolved in water and the change is reversible

Which of the following is a strong acid?

• Ethanoic acid (CH₃COOH)

• Nitric acid (HNO₃)

• Hydrofluoric acid (HF)

• Citric acid

Which of the following statements is true?

• If the H⁺ ion concentration in a solution increases by a factor of 10, the pH of the solution increases by 1

• If the H⁺ ion concentration in a solution increases by a factor of 10, the pH of the solution decreases by 1

Select the strong acids.

• CH₃COOH

• HCl

• H₂SO₄

• HNO₃

A weak acid always has a K_a value.

• True

• False

Litmus paper can tell you if a solution is acidic, neutral or basic by changing color when placed in a solution.  If you test a base with RED litmus paper, it will turn ____________.

• purple

• red

• blue

• pink

Which of the following is an acid?

• CO₂
• KOH
• NH₃
• HBr

Which of the following is basic?

• pH=7.85

• pH = 1.4

• pH = 6.92

• pH = 0

What is the pH of distilled water?

• pH 12

• pH 3

• pH 8

• pH 7

What does this hazard symbol mean?

• toxic

• flammable

• corrosive

• explosive