Chemical analysis (problem-solving)
A set of two and four mark exam-style questions on chemical analysis tests for various compounds, with a detailed set of answers to develop students' exam technique to maximise the marks they can achieve.
Perfect for exam practice and revision before the GCSE science exams.
Example questions from the resource:
1. The police suspected a wife of poisoning her husband by putting potassium bromide crystals into the salt cellar instead of common salt (sodium chloride). Describe tests the police could do to find out which chemical was inside the salt cellar. [4]
2. Deduce the identity of the following chemicals from these test results.
a. Green powder
On addition of hydrochloric acid, the green powder effervesced and gave off a gas which turned lime water milky. The resulting blue solution produced a pale blue precipitate when aqueous sodium hydroxide was added. [2]
b. Colourless liquid
When this colourless liquid was added to magnesium ribbon, it gave off a gas. This gas popped when tested with a lighted splint. When the liquid was added to washing soda (sodium carbonate), it gave off another gas which when bubbled through lime water turned it cloudy white (milky). On addition of silver nitrate solution to the colourless liquid, a white precipitate formed. [2]
