Problem 55
What will be the standard molar volume of He, if its density is \(0.1784 \mathrm{~g} / \mathrm{L}\) at STP? (a) \(11.2 \mathrm{~L}\) (b) \(22.4 \mathrm{~L}\) (c) \(5.6 \mathrm{~L}\) (d) \(2.8 \mathrm{~L}\)
Problem 56
In a mixture of gases, the volume content of a gas is \(0.06 \%\) at STP. Calculate the number of molecules of the gas in \(1 \mathrm{~L}\) of the mixture. (a) \(1.613 \times 10^{23}\) (b) \(6.023 \times 10^{23}\) (c) \(1.61 \times 10^{27}\) (d) \(1.61 \times 10^{19}\)
Problem 57
What will be the weight of CO having the same number of oxygen atoms as present in \(22 \mathrm{~g}\) of \(\mathrm{CO}_{2} ?\) (a) \(28 \mathrm{~g}\) (b) \(22 \mathrm{~g}\) (c) \(44 \mathrm{~g} \quad\) (d) \(72 \mathrm{~g}\)
Problem 60
Which of the following correctly represents \(180 \mathrm{~g}\) of water? (i) 5 moles of water (ii) 10 moles of water (iii) \(6.023 \times 10^{23}\) molecules of water (iv) \(6.023 \times 10^{24}\) molecules of water (a) (i) and (ii) (b) (i) and (iv) (c) (ii) ând (iv) (d) (ii) and (iii)
Problem 62
How many oxygen atoms will be present in \(88 \mathrm{~g}\) of \(\mathrm{CO}_{2} ?\) (a) \(24.08 \times 10^{23}\) (b) \(6.023 \times 10^{23}\) (c) \(44 \times 10^{23}\) (d) \(22 \times 10^{24}\)
Problem 63
What is the total number of electrons present in \(1.6 \mathrm{~g}\) of methane? (a) \(6.023 \times 10^{23}\) (b) 16 (c) \(12.04 \times 10^{23}\) (d) \(6.023 \times 10^{24}\)
Problem 64
A mixture having 2 g of hydrogen and \(32 \mathrm{~g}\) of oxygen occupies how much volume at NTP? (a) \(44.8 \mathrm{~L}\) (b) \(22.4 \mathrm{~L}\) (c) \(11.2 \mathrm{~L}\) (d) \(67.2 \mathrm{~L}\)
Problem 65
One atom of an element weighs \(3.32 \times 10^{-23} \mathrm{~g}\). How many number of gram atoms are there in \(20 \mathrm{~kg}\) of the element? (a) 2000 (b) 20 (c) 200 (d) 1000
Problem 66
Which of the following statements about Avogadro's hypothesis is correct? (a) Under similar conditions of temperature and pressure, gases react with each other in simple ratio. (b) Under similar conditions of temperature and pressure, equal volumes of all gases contain same number of molecules. (c) At NTP all gases contain same number of molecules. (d) Gases always react with gases only at the given temperature and pressure.
Problem 68
The mass of one mole of a substance in grams is called its (a) molecular mass (b) molar mass (c) Avogadro's mass (d) formula mass.
