CSEC Chemistry Paper 2 May/June 2010 - Free CXC Past Paper with Answers

The following statements were taken from a student's notebook. These statements are INCORRECT. In each case, you should state why the statement is incorrect and give the correct statement.

Sodium, magnesium, aluminium, silicon and chlorine are found in the same group in the periodic table. (Give your answer in terms of electron configuration.)

Reason:

Correct statement:

< ![CDATA[Of the elements magnesium and copper, magnesium will more readily oxidize an aqueous solution of zinc ions than copper will.

Reason:

Correct statement:

P and Q both have an electron configuration of 2, 8, 1. The mass numbers of P and Q are 23 and 24 respectively.

P reacts with water to produce a solution of its hydroxide and hydrogen gas. Write a balanced equation for the reaction between P and water.

Both P and Q give similar products when reacted with water. Account for this observation.

Q is radioactive. Radioactive substances are widely used in medicine, agriculture and industry. What is meant by the term 'radioactive'?

Give TWO uses of radioactive elements in medicine, agriculture or industry.

Use 1 Use 2

Using dot-and-cross diagrams, show the bonding between Q and oxygen. [ $^{16}_8$O ]

Define 'structural isomerism'.

Draw fully displayed structures of but-1-ene and but-2-ene. But-1-ene But-2-ene

Draw and name ONE OTHER structural isomer of $C_4H_8$.

State ONE physical property of $C_4H_8$.

Ethanol reacts with different reagents to form products with the functional groups shown in Table 3.

What is meant by a 'functional group'?

Complete Table 3 by a) identifying the reagents or reaction conditions b) drawing the fully displayed structures of the products.

TABLE 3: REACTIONS OF ETHANOL

A pink solution of aqueous acidified potassium manganate(VII) is decolourised by the addition of ferrous($Fe^{2+}$) ions. The chemical equation for the reaction is $MnO_4^-(aq) + 5 Fe^{2+}(aq) + 8 H^+(aq) \rightarrow Mn^{2+}(aq) + 5 Fe^{3+}(aq) + 4 H_2O$. Identify the oxidizing and reducing agents in the equation, and explain your answer.

Iron(II) oxide reacts with dilute sulphuric acid to give a pale green solution. Write the equation for the reaction between iron(II) oxide and dilute sulphuric acid.

State whether the reaction in (ii) above is acid-base or redox, and explain your answer.

What is meant by 'fermentation,' as it relates to the manufacture of rum?

Write the equation for the fermentation process defined in (i).

Suggest ONE material that could be used to produce wine by fermentation, and give a reason for your suggestion.

Write the chemical formula for ONE ore of iron.

Outline the steps involved in the extraction of iron from its ore. Write a balanced chemical equation for EACH step.

Stainless steel, an alloy of iron, is used to make cooking utensils. Suggest TWO reasons why stainless steel is used instead of iron for making cooking utensils.

Besides cooking utensils, state ONE other use of iron or its alloys.

Name the compound of iron that is found in the blood and explain how a lack of iron would affect the human body.

Almost all animals eat their food raw, whereas humans tend to cook their food. Give TWO reasons why humans may need to cook their food.

Egg white is a transparent liquid in its natural state.

What does egg white look like when it is cooked?

What is the effect of heat on the protein of the egg?

Table 4 shows three different methods which can be used to cook a leg of lamb.

TABLE 4: METHODS FOR COOKING LAMB

Select the method by which the lamb will take the LONGEST to cook.

Outline the principles involved in the functioning of the pressure cooker.

Suggest TWO benefits of using the pressure cooker in Method 3.

Explain how the pineapple functions in cooking the lamb in Method 2.

How does this differ from the use of the pressure cooker in Method 3?

Explain how heat affects the Vitamin C in the pineapple.