Which noble gas is radioactive and is produced as a decay product of uranium and thorium?

• A. Argon
• B. Krypton
• C. Radon
• D. Neon

An acid is a substance which in the presence of water produces

• A. salts
• B. oxygen
• C. effervescence
• D. hydroxonium ions

Which of the following compounds will undergo additional reactions?

• A. Ethyne
• B. Butane
• C. Pentane
• D. Tetrachloromethane

120cm of hydrogen were sparked with 60cm of oxygen at 110°C. What was the volume of steam produced? Theequation for the reaction is 2H₂(g) + O₂(g) -------> 2H2_O(g)

• A. 30cm³
• B. 60cm³
• C. 90cm³
• D. 120cm³

The formula (CH₃)₃COH is that of a

• A. polyhdric alkanol
• B. secondary alkanol
• C. tertiary alkanol
• D. primary alkanol

(a)(i) Define entropy

(ii) What term is used to describe a reaction in which heat is absorbed from the surrounding?

(b) State two conditions that can lead to ineffective collisions during a chemical reaction.

Calculate the mass of chlorine gas which occupies a volume of 1.12 dm³ a volume of 1.12 dm³ at s.t.p [Cl = 35.5, 1 mole og gas occupies 22.4 dm³ at s. t. p ]

• A. 1.80g
• B. 3.55g
• C. 7.10g
• D. 15.50g

10.0 dm3 of water was added to 2.0 mol dm-3 of 2.5dm^3 solution of HCl. What is the concentration of the final solution in mol/dm^3?

• A) 0.4
• B) 8.0
• C) 2.0
• D) 0.5

A sodium atom and a sodium ion have the same

• A. number of neutrons
• B. number of electrons
• C. electric charge
• D. electronic structure

(a) State Gay Lussac's Law.

(b) Carbon (II) oxide reacted with oxygen to form carbon (IV) oxide in a see tube.

(i) Write a balanced equation for the reaction.

(ii) If 40 cm\(^3\) of the carbon (II) oxide were mixed with cm\(^3\) of oxygen,

I. calculate the volume of carbon (IV) oxide produced

II. which reactant is in excess and how much?

III. what was the total volume of the gaseous mixture at the end of the reaction?

(c) Consider the following oxides: CaO, SiO\(_2\), CO, NO\(_2\) and ZnO. Which of the oxide(s)

(i) is an acidic oxide that is insoluble in water?

(ii) reacts with water to give alkaline solution?

(iii) is amphoteric?

(iv) is neutral?

(v) is/are gaseous at room temperature?

(d) Explain why

(i) colourless concentrated trioxonitrate (V) acid turns yellow,

(ii) dilute trioxonitrate (V) acid does not liberate hydrogen when it reacts with magnesium.

(e) Write a chemical equation for the thermal decomposition of (i) Cu(NO\(_3\))\(_{2(g)}\)

(ii) NH\(_4\)NO\(_{3(g)}\)