CSEC Chemistry Paper 2 May/June 2024 - Free CXC Past Paper with Answers

Define the following terms.

Atomic number

Mass number

Isotopes

Use a dot and cross diagram to show the bonding present in oxygen gas.

There are many uses of radioactive isotopes in everyday life. List ANY THREE uses of radioactive isotopes.

Carbon burns completely in excess oxygen to produce carbon dioxide. Write a balanced chemical equation, including state symbols, to show this reaction.

Carbon burns in limited oxygen supply to produce carbon monoxide. Write a balanced chemical equation, including state symbols, to show this reaction.

Compounds A and B are straight-chain hydrocarbons whose molecular formulas are $C_3H_{12}$ and $C_4H_{14}$ respectively.

State ONE natural source of hydrocarbons.

State TWO uses of Compound B.

Draw the FULLY displayed structure of Compound A.

Draw the FULLY displayed structure of Compound A.

Draw the FULLY displayed structure of Compound B.

List ANY FOUR general characteristics of a homologous series.

Deduce the homologous series to which Compounds A and B belong.

Compound B ($C_4H_{14}$) burns completely in oxygen to produce carbon dioxide ($CO_2$) and water (). Write a balanced chemical equation, including state symbols, for this reaction.

Explain metallic bonding in metals.

Give the reason why metals conduct electricity in solid form.

State ANY TWO harmful effects of lead and its compounds on living things and their environment.

A chemistry student conducted a series of experiments using an electrolytic cell to test the conductivity of magnesium chloride. The materials used to set up the apparatus and the student's observations were recorded in Table 2 below.

TABLE 2: MATERIALS USED TO SET UP EXPERIMENTS AND OBSERVATIONS

Explain why the bulb did not light in Experiments 1 and 3.

Experiment 1

Experiment 3

Explain why the bulb lit in Experiment 2.

State the process that took place in Experiment 2.

Magnesium readily reacts with oxygen in the air. Write a balanced chemical equation for this reaction.

Proteins and starch are examples of natural polymers which are formed through the process of condensation polymerization.

Define the term 'polymer'.

Define the term 'condensation polymerization'.

The manufacture of ethanol makes use of the fermentation process.

Define the term 'fermentation'.

Write a balanced chemical equation, including state symbols, to show the process of fermentation.

Draw the FULLY displayed structure of ethanol.

During a demonstration of the wine-making process in the school's food laboratory, a technician separated a pure sample of ethanol. However, the flask was not labelled and water was accidentally poured into the sample.

Using a line diagram, draw and label the apparatus that could be set up in the chemistry laboratory to obtain the pure ethanol from the contaminated sample.

Water is called the universal solvent because it dissolves many substances. Epsom® salt and Alka Seltzer® work by dissolving in water.

Explain why water is a good solvent.

State TWO properties of water other than it is a good solvent.

State ANY TWO other compounds that dissolve in water.

Continuous use of Epsom® salt in water may cause hardness of water. This does not happen with Alka Seltzer®.

State the type of water hardness caused by dissolving Epsom® salt in water.

Explain why Epsom® salt causes hardness of water.

Explain why boiling the water will not remove the hardness caused by Epsom® salt.

Identify TWO salts that cause hardness of water and can be removed by boiling.

When used as an antacid, Alka Seltzer® neutralizes the hydrochloric acid ($HCl$) in the stomach. Write a balanced chemical equation, including state symbols, to illustrate this process.