Oxygen oxidises ethyne to carbon dioxide and water as shown by the equation :

$2{\mathrm{C}}_2{\mathrm{H}}_2+5{\mathrm{O}}_2\to 4{\mathrm{CO}}_2+2{\mathrm{H}}_2\mathrm{O}$

What volume of ethyne gas at STP is required to produce 8.4cm³ of carbon dioxide at STP? (H= 1, C=12, O= 16)

Oxygen oxidises Ethyne to Carbon dioxide and water as shown by the equation
$2{\mathrm{C}}_2{\mathrm{H}}_2+5{\mathrm{O}}_2\to 4{\mathrm{CO}}_2+2{\mathrm{H}}_2\mathrm{O}$
What volume of Ethyne gas at STP is required to produce $8.4{\mathrm{dm}}^3$ of carbon dioxide at STP?
(H=1, C=12 and O=16)

(a) What volume of oxygen is required to burn completely a mixture of 22.4 dm³ of methane and 11.2 dm³ of hydrogen into carbon dioxide and steam? Equations of the reactions are given below:
CH₄ + 2O₂ $\stackrel{}{\to }$ CO₂ + 2H₂O
2H₂ + O₂ $\stackrel{}{\to }$ 2H₂O
(Assume that all volumes are measured at STP)

(b) The gases hydrogen, oxygen, carbon dioxide, sulphur dioxide and chlorine are arranged in order of their increasing relative molecular mass. Given 8 g of each gas at STP, which gas will contain the least number of molecules and which gas the most?

(a) (i) A compound has the following percentage composition by mass: carbon 14.4%, hydrogen 1.2% and chlorine 84.5%. Determine the empirical formula of this compound. Work correct to 1 decimal place. (H = 1; C = 12; Cl = 35.5)
(ii) The relative molecular mass of this compound is 168, so what is its molecular formula?
(iii) By what type of reaction could this compound be obtained from ethyne?

(b) From the equation:
C + 2H₂SO₄ $\stackrel{}{\to }$ CO₂ + 2H₂O + 2SO₂
Calculate:
(i) the mass of carbon oxidised by 49 g of sulphuric acid (C = 12; relative molecular mass of sulphuric acid = 98).
(ii) the volume of sulphur dioxide measured at STP, liberated at the same time.
(Volume occupied by 1 mole of a gas at STP is 22.4 dm³).