Correct Answer: B. selling securities in the open market

Correct Answer: D. close rapport between players and spectators.

Correct Answer: D. Machinery and transport equipment

Correct Answer: B. 1.90 x 10^-5K^-1

Explanation

\(\alpha\) = \(\frac{\Delta}{3} = \frac{5.7 \times 10^{-5}}{3}\)

= 1.90 x 10^-5K^-1

Correct Answer: C. \(\frac{4}{5}\)

Explanation

PQ = \(\begin {pmatrix} 2 & 3\\ -4 & 1\end {pmatrix}\) = \(\begin {pmatrix} 6 \\ 8 \end {pmatrix}\) = \(\begin {pmatrix} 36 \\ - 16\end {pmatrix}\)

\(\begin {pmatrix} 36 \\ -16 \end {pmatrix} \) = k = \(\begin {pmatrix} 45 \\ -20 \end {pmatrix} \)

k = \(\frac{36}{45}\)

= \(\frac{4}{5}\)

Correct Answer: D) ZnO

Correct Answer: A. MC = MR

Explanation

(a)(i) Hard water is water which will not readily form lather with soap.

(ii) 1. Calcium tetraoxosulphate (IV) 2. Calcium hydrogen trioxocarbonate (IV) 3. Magnesium tetraoxosulphate (VI) 4. Magnesium hydrogen trioxocarbonate (IV).

(iii)(a) Heating the water to boiling/distillation (b) Addition of calculated amount of calcium hydroxide [Ca(OH)\(_2\)] (c) Addition of washing soda crystals to the water [Na\(_2\)CO\(_3\)] (d) Ion exchange resin/permutit method.

(b)(i) Sulphur air or oxygen

(ii) 2SO\(_{2(g)}\) +O\(_{2(g)}\) \(\rightleftharpoons\) 2SO\(_{3(g)}\)

(iii) V\(_2\)O\(_5\) / Vanadium (V) oxide.

(c)(i) Use of Na\(_2\)SO\(_4\)

(a) Water softener (b) In glass or paper manufacturing (c) As analytical reagent (d) As purgative (e) In the manufacture of detergents .

(ii) Mass of salt per 30 cm\(^3\) of saturated solution = 1.80g.

1000 cm\(^3\) of saturated solution contains = \(\frac{1000 \times 1.80}{30}\)

= 60g.

Molar mass of Na\(_2\)CO\(_3\) = 23 x 2 + 12 x 1 + 16 x 3 = 106g.

Solubility of Na\(_2\)CO\(_3\) = \(\frac{60}{106}\) = 0.566 mole dm\(^3\).

(d)(i) Activated complex is the intermediate (complex) that reactants must attain in order to form a product or it is a temporary species formed by reactant molecules as a result of collision before the products are formed.

(ii) A collision may fail to produce a chemical reaction if the energy of the colliding particles is less than activation energy / if the reactant are not properly aligned.

(a)(i) Hard water is water which will not readily form lather with soap.

(ii) 1. Calcium tetraoxosulphate (IV) 2. Calcium hydrogen trioxocarbonate (IV) 3. Magnesium tetraoxosulphate (VI) 4. Magnesium hydrogen trioxocarbonate (IV).

(iii)(a) Heating the water to boiling/distillation (b) Addition of calculated amount of calcium hydroxide [Ca(OH)\(_2\)] (c) Addition of washing soda crystals to the water [Na\(_2\)CO\(_3\)] (d) Ion exchange resin/permutit method.

(b)(i) Sulphur air or oxygen

(ii) 2SO\(_{2(g)}\) +O\(_{2(g)}\) \(\rightleftharpoons\) 2SO\(_{3(g)}\)

(iii) V\(_2\)O\(_5\) / Vanadium (V) oxide.

(c)(i) Use of Na\(_2\)SO\(_4\)

(a) Water softener (b) In glass or paper manufacturing (c) As analytical reagent (d) As purgative (e) In the manufacture of detergents .

(ii) Mass of salt per 30 cm\(^3\) of saturated solution = 1.80g.

1000 cm\(^3\) of saturated solution contains = \(\frac{1000 \times 1.80}{30}\)

= 60g.

Molar mass of Na\(_2\)CO\(_3\) = 23 x 2 + 12 x 1 + 16 x 3 = 106g.

Solubility of Na\(_2\)CO\(_3\) = \(\frac{60}{106}\) = 0.566 mole dm\(^3\).

(d)(i) Activated complex is the intermediate (complex) that reactants must attain in order to form a product or it is a temporary species formed by reactant molecules as a result of collision before the products are formed.

(ii) A collision may fail to produce a chemical reaction if the energy of the colliding particles is less than activation energy / if the reactant are not properly aligned.

Correct Answer: C. Radiation

Correct Answer: A. vary continuously