ExpertEasy2 marksStructured
AQA GCSE · Question 07.9 · Chemical analysis
The student tests the gas produced using a burning splint.
Name the gas the student is testing for.
Give the result of a positive test for this gas.
The student tests the gas produced using a burning splint.
Name the gas the student is testing for.
Give the result of a positive test for this gas.
How to approach this question
1. **Name of gas:** Consider the reaction: magnesium (a metal) + hydrochloric acid. Recall the general word equation for the reaction of a metal with an acid. This will tell you the gas produced.
2. **Result:** Recall the standard chemical test for this gas using a lit splint and the sound it makes.
Full Answer
Name of gas: Hydrogen
Result: A lit splint makes a squeaky pop sound.
The reaction between magnesium and hydrochloric acid is:
Magnesium + Hydrochloric Acid → Magnesium Chloride + Hydrogen
Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g)
The gas produced is hydrogen.
- **Name of gas:** Hydrogen (H₂)
- **Test and Result:** The standard test for hydrogen gas is to place a lit splint into the mouth of a test tube containing the gas. If hydrogen is present, it will ignite with a characteristic 'squeaky pop' sound. This sound is caused by a mini-explosion as the hydrogen rapidly combusts with oxygen in the air.
Common mistakes
✗ Naming the wrong gas (e.g., oxygen, carbon dioxide).
✗ Giving the wrong test result (e.g., "relights a glowing splint" which is the test for oxygen, or "turns limewater cloudy" which is for CO₂).
Practice the full AQA GCSE Chemistry Foundation Tier Paper 2
60 questions · hints · full answers · grading
More questions from this exam
Q01.1This question is about copper sulfate. Blue copper sulfate turns white when it is heated. The wor...EasyQ01.2What does the symbol ⇌ mean?EasyQ01.3Complete the sentence.
The colour change when water is added to anhydrous copper sulfate is white...EasyQ01.4A student heats 2.5 g of hydrated copper sulfate in a test tube. 0.9 g of water is given off. The...EasyQ01.5Calculate the percentage of water contained in 2.5 g of hydrated copper sulfate.
(Mass of water =...Medium