How many atoms of chlorine are required to saturate the double bonds of a compound containing a triene?

A. 2

B. 3

C. 4

D. 5

E. 6

Which of the following gases is absorbed from the air dun photosynthesis?

A. Carbon (II) oxide

B. Carbon (IV) oxide

C. Nitrogen

D. Noble gases

E. Oxygen

X = - log₁₀ H⁺]

What does X stand for in the expression above?

A. Degree of acidity

B. Enthalpy change

C. Equilibrium constant

D. Ionic product of water

E. Solubility product

During the extraction of iron in the blast furnance, slag is produced using

A. carbon

B. crylite

C. limestone

D. oxygen

E. sulphur

Brain tumors can be located by using an isotope of

A. carbon - 14

B. iodine 131

C. technetium 99

D. uranium235

E. uranium 238

What volume of carbon (IV) oxide in dm ³ is produced at s.t.p. when 2.50g of CaCO₃ reacts with excess acid according to the following equation? CaCO₃(s) + 2HCI(aq) → CaCl₂(aq) + H₂O(1) + CO₂(g)

[CaCO₂ 100; molar volume of a gas at s.t.p. = 22.4dm ³]

A. 0.28

B. 0.56

C. 2.24

D. 5.6

E. 11.2

The following equations represent redox reactions EXCEPT

A. Ba²⁺(aq) + SO^2-₄ (aq) → BaSO₄(s)

B. Cl₂(g) + 2Br^- (aq) → 2CI ^- (aq) + Br₂(g)

C. Fe²⁺(aq) + ½ C I₂(aq) → Fe³⁺ (aq) + CI^-(aq)

D. 2Fe³⁺(aq) + Sn²⁺(aq) → 2Fe²⁺(aq) Sn⁴⁺ (aq)

E. Zn(s) + CU²⁺(aq) → Zn²⁺(aq) + CU(s)