OCR A Level Chemistry A PAG 4 Qualitative analysis of ions Exam Questions and Mark Scheme.

, OCR A Level Chemistry A (H432) Chemistry B (H433)
PAG 4: Qualitative analysis of ions
Practice Exam Questions and Mark Scheme

This resource includes exam questions from both Chemistry A and Chemistry B. It is not designed as a
topic test but is instead intended as a document to support the teaching and learning of Module 1 –
Development of practical skills in chemistry.


1. Three qualitative tests are carried out on a solution of an unknown compound.

Test 1: On heating with NaOH(aq), a pungent smelling gas evolves which turns red litmus paper
blue.

Test 2: On addition of AgNO3(aq), a white precipitate forms which is soluble in dilute NH3(aq).

Test 3: On addition of Na2CO3(aq), there is no visible reaction.

What is the unknown compound?

A. ammonium bromide, NH4Br
B. ammonium chloride, NH4Cl
C. hydrochloric acid, HCl
D. sodium chloride, NaCl

Your answer
[1]


2. Four pairs of solutions are mixed.

Which pair of solutions forms a white precipitate?

A NH4Cl (aq) and NaOH(aq)
B KBr(aq) and AgNO3(aq)
C FeCl 3(aq) and NH3(aq)
D Cr2(SO4)3(aq) and BaCl 2(aq)

Your answer [1]



3. Which of the following is a correct statement about the test for Fe2+ ions in solution?

A. add NaOH(aq); brown precipitate formed, soluble in NH3(aq)
B. add NaOH(aq); brown precipitate formed, insoluble in NH3(aq)
C. add NaOH(aq); green precipitate formed, soluble in NH3(aq)
D. add NaOH(aq); green precipitate formed, insoluble in NH3(aq)


Your answer

[1]




Created in ExamBuilder 1 © OCR 2020