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Acids, bases and titration — Question 27

QCAA 2022, Paper 1 · 5 marks

Q27 · 2022 · Paper 1Unclassified5 marks

QUESTION 27 (5 marks)

Five colourless 0.1 M solutions of NH3, HCl, KOH, H2SO4 and CH3CH2COOH have lost their labels. The substances are randomly relabelled A, B, C, D and E. The conductivity of each solution and the colour of the solution when phenol red was added are shown.

Solution

Conductivity (S/m)

Colour with phenol red

A

4.1

yellow

B

0.14

red

C

0.08

yellow

D

6.7

yellow

E

4.9

red

Identify the five solutions. Explain your reasoning.

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