Chemistry Past Questions and Answers

The molar ratio of carbon to hydrogen of a volatile liquid compound is 1: 2. 0. 12 g of the liquid on evaporation at s.t.p. gave 32 cm<sup style='font-size: smaller;'>3</sup> of vapour. The molecular formula of the liquid is<br/>[G.M.V =22.4 dm <sup style='font-size: smaller;'>3</sup>, C = 12, H = 1]

20.00 cm <sup style='font-size: smaller;'>3</sup> of a solution containing 0.53 g of anhydrous Na<sub style='font-size: smaller;'>2</sub>CO<sub style='font-size: smaller;'>3</sub> in 100 cm<sup style='font-size: smaller;'>3</sup> requires 25.00 cm<sup style='font-size: smaller;'>3</sup> of H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> for complete neutralisation. The concentration of the acid solution in moles per dm is [H =1, C = 12, O = 16, Na =23, S = 32]

The minimum volume of oxygen required for the complete combustion of a mixture of 10cm <sup style='font-size: smaller;'>3</sup> of CO and 15 cm <sup style='font-size: smaller;'>3</sup> of H <sup style='font-size: smaller;'>2</sup> is

What is the partial pressure of hydrogen gas collected <br/>over water at standard atmospheric pressure and 25 <sup style='font-size: smaller;'>o</sup>C if the saturation vapour pressure of water at saturation vapour pressure of water is 23 mm Hg at that temperature?

The atomic radius of Li, Na and K are 1: 33A, 1. 54A and 1. 96A res pectively. Which of the following explaqins this gradation in atomic radius?