Learners' AlleyDesigned by Khow Willard

Practical Chemistry and Qualitative Analysis

Set AConcept Practice

Name

Time 35 minutes

Total 30 marks

From the lesson

23 marks

Which apparatus measures exactly 25.0 cm³ of acid most accurately?

Ameasuring cylinder

Bpipette

Cbeaker

Dgas syringe

Answer [1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

Which burette reading is recorded correctly?

A23 cm³

B23.4 cm³

C23.45 cm³

D23.453 cm³

Answer [1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

Which cation gives a white precipitate with both aqueous sodium hydroxide and aqueous ammonia, soluble in excess of both?

AAl³⁺

BCa²⁺

CZn²⁺

DMg²⁺

Answer [1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

A student adds dilute hydrochloric acid to a solution, then aqueous silver nitrate, and sees a white precipitate. Why does this not prove that the solution contained chloride ions?

ASilver nitrate does not react with chloride ions.

BThe hydrochloric acid itself added chloride ions.

CSilver chloride is soluble in acid.

DThe precipitate should be yellow.

Answer [1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

Repeated titres agree closely but are all larger than the true value. Which change would make them more accurate?

ARepeat the titration more times.

BRead the burette with the eye level with the meniscus.

CUse a larger conical flask.

DAverage all the titres.

Answer [1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

(a)

Give one advantage of a burette over a measuring cylinder.

[1]

(b)

Give one disadvantage of a pipette.

[1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

(a)

Gas X is less dense than air and insoluble in water. Suggest a method to collect it.

[1]

(b)

Gas Y reacts with acids. Name a drying agent for it and explain your choice.

[1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

(a)

Why is the conical flask swirled during a titration?

[1]

(b)

A burette reads 1.20 cm³ at the start and 24.65 cm³ at the end-point. Find the titre.

[1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

(a)

Compound X contains aluminium, calcium or zinc ions. Describe how you would find out which.

[2]

(b)

A solution gives a light blue precipitate with aqueous ammonia that dissolves in excess. Give the colour of the final solution and the cation.

[1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

(a)

Describe the test for sulfate ions.

[1]

(b)

A solution contains sodium chloride or sodium iodide. How would you tell which?

[1]

(c)

How would you tell a sulfite from a sulfate?

[1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

(a)

A reaction gives off a colourless, odourless gas. Which gases could it be, and how would you tell them apart?

[2]

(b)

Describe how to tell chlorine, ammonia and hydrogen apart.

[2]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

(a)

Which has the larger percentage uncertainty: 20.0 cm³ in a measuring cylinder (±0.5 cm³) or 2.00 g on a balance (±0.01 g)?

[1]

(b)

Five readings of a 5.00 g mass are 5.21 g, 5.20 g, 5.22 g, 5.21 g and 5.20 g. Are they accurate, precise, both or neither?

[1]

Learners' Alley, Practical Chemistry and Qualitative Analysis slides

Practice

7 marks

Which apparatus is most suitable to measure 27.8 cm³ of a solution?

Aburette

Bbeaker

Cpipette

Dmeasuring cylinder

Answer [1]

Source: 2024 BLSS O Prelim P1 Q3

A student measures the time taken for 1.0 g of magnesium to dissolve in 25.0 cm³ of dilute hydrochloric acid. A stopwatch and electronic balance are provided in the set-up.

What additional apparatus is essential to complete the experiment?

1 measuring cylinder
2 pipette
3 gas syringe

A1 only

B2 only

C1 and 2

D1 and 3

Answer [1]

Source: 2024 Bukit View O Prelim P1 Q1

A student carried out an experiment involving the reaction between calcium carbonate and dilute hydrochloric acid. Based on the experimental results, a graph of volume of gas produced against time was plotted. Which apparatus were used by the student to make the necessary measurements?

Aburette, pipette and stopwatch

Belectronic balance and gas syringe

Cgas syringe and stopwatch

Dpipette and stopwatch

Answer [1]

Source: 2024 SMSS O Sec3 P1 Q1

Two methods of gas collection are upward delivery and displacement of water. Which row correctly shows whether each of these methods could be used to collect the gas?

Adenser than air and soluble: upward delivery yes, displacement of water yes

Bless dense than air and soluble: upward delivery yes, displacement of water no

Cdenser than air and insoluble: upward delivery yes, displacement of water no

Dless dense than air and insoluble: upward delivery no, displacement of water yes

Answer [1]

Source: 2025 Compassvale O Prelim P1 Q1

Which row shows the correct drying agent and the corresponding gas that can be collected by upward delivery into a gas jar? Each option gives the drying agent, then the gas collected.

Aanhydrous calcium oxide, carbon dioxide

Banhydrous calcium oxide, ammonia

Cconcentrated sulfuric acid, sulfur dioxide

Dconcentrated sulfuric acid, chlorine

Answer [1]

Source: 2024 Woodlands O Prelim P1 Q1

Aqueous sodium hydroxide is neutralised by dilute hydrochloric acid in a titration. 25.0 cm³ of aqueous sodium hydroxide is measured into a conical flask using a …1… and a few drops of methyl orange are added. The dilute hydrochloric acid is added using a …2…. The end-point is reached when the methyl orange turns …3…. Which words complete blanks 1, 2 and 3?

	1	2	3
A	burette	pipette	red
B	burette	pipette	orange
C	pipette	burette	orange
D	pipette	burette	red

Arow A

Brow B

Crow C

Drow D

Answer [1]

2024 Zhenghua O Prelim P1-P3 Q1

When testing for chloride ions with silver nitrate, the solution must be acidified with dilute nitric acid. What is the purpose of the nitric acid?

Ato act as a catalyst

Bto oxidise the chloride ion

Cto prevent precipitation of silver carbonate

Dto prevent the decomposition of any silver chloride formed

Answer [1]

2024 BLSS O Prelim P1 Q21