C10.4 GCSE Carboxylic Acids and Esters AQA

What gas is produced when magnesium reacts with ethanoic acid?

• hydrogen

• carbon dioxide

• oxygen

• chlorine

What gas is produced when potassium carbonate reacts with ethanoic acid?

• hydrogen

• carbon dioxide

• oxygen

• chlorine

Complete the word equation for the reaction:

ethanoic acid + potassium carbonate → _________ ________+ carbon dioxide + water

(a)  

Ethanoic acid is described as a weak acid. Explain what this means in terms of ionisation

• fully ionised

• partially ionised

• deionised

Complete the following equation, which show what happens when ethanoic acid dissolves in water.

CH₃COOH(aq)⋚ CH₃COO^– (aq) + _______

• H

• H^-

• H⁺

• H₂

Explain why the pH of 0.1 mol/dm³ hydrochloric acid is lower than the pH of 0.1 mol/dm³ ethanoic acid

• Hydrochloric acid is a strong acid so is fully ionised.It has a higher concentration of H⁺ ions, so a lower pH.

• Hydrochloric acid is a weak acid so is fully ionised.It has a higher concentration of H⁺ ions, so a lower pH.

• Hydrochloric acid is a strong acid so is partially ionised.It has a higher concentration of H⁺ ions, so a lower pH.

• Hydrochloric acid is a strong acid so is fully ionised.It has a lower concentration of H⁺ ions, so a lower pH.

What is the role of sulfuric acid in the reaction to make esters?

• weak acid

• hydrogen ion acceptor

• catalyst

• partially ionises

Esters have distinctive sweet smells, and are volatile liquids. What does volatile mean?

• flows easily

• catches fire easily

• evaporates easily

• colours easily

Carboxylic acids dissolve in water to form solutions with a typical pH of around (a)   ? (type in a number)

What are some common uses of esters? (Select all that apply)

• perfumes

• flavourings

• clothing

• nappies