Solved 2017 Question Paper ICSE Class 10 Chemistry — Question 12
Back to all questionsA gas cylinder can hold 1 kg of hydrogen at room temperature and pressure:
(i) Find the number of moles of hydrogen present.
(ii) What weight of CO2 can the cylinder hold under similar conditions of temperature and pressure? (H= 1, C = 12, O = 16)
(iii) If the number of molecules of hydrogen in the cylinder is X, calculate the number of CO2 molecules in the cylinder under the same conditions of temperature and pressure.
(iv) State the law that helped you to arrive at the above result.
(i) 2 g of hydrogen gas = 1 mole
∴ 1000 g of hydrogen gas = = 500 moles.
(ii) Molar mass of CO2 = C + 2(O) = 12 + 2(16) = 44 g
1 mole of carbon dioxide = 44 g
∴ 500 moles of carbon dioxide = 44 x 500 = 22,000 g = 22 kg.
Hence, Weight of carbon dioxide in cylinder = 22 kg
(iii) According to Avogadro's law — Equal volumes of all gases under similar conditions of temperature and pressure contain equal number of molecules.
∴ molecules in the cylinder of carbon dioxide = X.
(iv) Avogadro's law — Equal volume of all gases under similar conditions of temperature and pressure contain equal number of molecules.