A Level Quiz (Periodic Table, Groups 2&7)

1 A solid is soluble in water and produces steamy acidic fumes with concentrated sulfuric acid. The solid could be

• A potassium carbonate.
• B magnesium sulfate.
• C silver chloride.
• D sodium chloride.

2. Two layers form when the non-polar solvent cyclohexane (density 0.78 g cm−3) is mixed with a dilute solution of aqueous iodine (density 1.03 g cm−3) and left to stand. The colours of the layers are:

• A
• B
• C
• D

3 Anhydrous calcium nitrate decomposes on heating.Decomposition occurs quite easily because of the

• A polarisation of the calcium ion by the nitrate ion.
• B polarisation of the nitrate ion by the calcium ion.
• C distortion of the calcium electron cloud by the nitrate ion.
• D repulsion of the nitrate electron cloud by the calcium ion.

4 Which of the following is the correct equation for the decomposition of the corresponding nitrate?

• A
• B
• C
• D

5 Which of the following describes the appearance of iodine under the stated conditions?

• A
• B
• C
• D

6 In aqueous solution, manganate(VI) ions disproportionate into manganate(VII) ions and manganese(IV) oxide when carbon dioxide is bubbled through the solution. What is the role of the carbon dioxide? The ionic equation for the reaction is

• A lower the pH of the solution.
• B raise the pH of the solution.
• C oxidize the manganate(VI) ions.
• D reduce the manganate(VI) ions.

7 Which is not a disproportionation reaction?

• A
• B
• C
• D

8

• A
• B
• C
• D

9 When a flame test is carried out on calcium iodide, the colour of the flame is

• A yellow-red.
• B pale green.
• C purple.
• D crimson.

10 What would be the experimental observations if chlorine gas was bubbled through potassium iodide solution, followed by the addition of cyclohexane?

• A The solution turns brown, then two layers are produced and the top layer is purple.
• B A white precipitate is formed, which then dissolves to leave a colourless solution.
• C Bubbles of gas are seen and then a brown precipitate is formed.
• D The solution remains colourless, and then two layers are seen with the bottom layer being brown.