Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Chemical Tests
68 practice questions
Topics covered
Practice questions
21–30 of 68
Question 21
1 mark · Easy
Answer and see the solution →State the name of the gas given off when dilute hydrochloric acid is added to a carbonate compound.
Question 22
3 marks · Easy
Answer and see the solution →(a)[1 mark]State the reagent added to a sample to test for carbonate ions.
(b)[1 mark]Describe what you would observe if carbonate ions are present after adding this reagent.
(c)[1 mark]Explain how you would confirm that the gas produced is carbon dioxide.
Question 23
3 marks · Easy
Answer and see the solution →Test results for carbonate ions. Sample Dilute acid added Fizzing observed Gas turns limewater cloudy X Yes Yes Yes Y Yes No - Z Yes Yes No (a)[1 mark]Which sample(s) most likely contain carbonate ions? Explain your answer.
(b)[1 mark]Suggest a possible identity for the gas produced from sample Z.
(c)[1 mark]Explain why sample Y does not give the same results as X.
Question 24
1 mark · Easy
Answer and see the solution →Write the ionic equation for the reaction between a carbonate ion and an acid.
Question 25
3 marks · Easy
Answer and see the solution →(a)[2 marks]A teacher gives you a sample to test for carbonate ions. Describe fully how you would carry out this test.
(b)[1 mark]State how you would know if carbonate ions are present.
Question 26
2 marks · Easy
Answer and see the solution →A student tests 0.20 g of sodium carbonate powder by adding excess dilute hydrochloric acid. Calculate the maximum volume of carbon dioxide gas produced at room temperature and pressure (RTP), assuming that 1 mole of gas occupies 24 dm^3 at RTP. (Relative formula mass of Na2CO3 = 106)
Question 27
2 marks · Easy
Answer and see the solution →A powder is suspected to contain carbonate ions (CO3^2-). Describe the two steps you would take to confirm the presence of carbonate ions in the powder and explain what results would show that carbonate ions are present.
Question 28
2 marks · Easy
Answer and see the solution →A student wants to test for carbonate ions using dilute hydrochloric acid. She needs at least 0.22 g of carbon dioxide gas (CO2) to turn limewater cloudy. Calculate the minimum mass of sodium carbonate (Na2CO3) required to produce 0.22 g of CO2, assuming all of the carbonate reacts and only this gas is formed.
Relative atomic masses: Na = 23, C = 12, O = 16
Question 29
4 marks · Normal
Answer and see the solution →A student tests a solid substance to find out if it contains carbonate ions. The student adds dilute sulfuric acid and observes bubbles of gas. They collect the gas and pass it through limewater.
(a)[1 mark]Write the ionic equation for the reaction between carbonate ions () and sulfuric acid.
(b)[1 mark]State the identity of the gas formed.
(c)[1 mark]Describe the observed result when the gas is bubbled through limewater.
(d)[1 mark]Explain how these observations confirm that the original solid contained carbonate ions.
Question 30
4 marks · Normal
Answer and see the solution →A student is testing three white powders (A, B and C) for carbonate ions using dilute hydrochloric acid and limewater. Their results are shown:
Student's results for carbonate test Powder Acid added Fizzing observed? Limewater turns cloudy? A Yes Yes Yes B Yes No No C Yes Yes No (a)[2 marks]Which powder(s) definitely contain carbonate ions? Explain your answer.
(b)[2 marks]Suggest a reason why powder C showed fizzing but did not turn limewater cloudy.