Problem 80
Lactose commonly used as a binder in tablets has a molecular weight \(342 .\) What weight of \(\mathrm{CO}_{2}\) would be formed when \(1 / 12\) mole of this compound is burnt completely? \(\left(\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}+12 \mathrm{O}_{2} \longrightarrow 12 \mathrm{CO}_{2}+11 \mathrm{H}_{2} \mathrm{O}\right)\) \((1) 12 \mathrm{~g}\) (2) \(44 \mathrm{~g}\) (3) \(4.4 \mathrm{~g}\) (4) \(440 \mathrm{~g}\)
Problem 81
What mole ratio of molecular chlorine \(\left(\mathrm{Cl}_{2}\right)\) to molecular oxygen \(\left(\mathrm{O}_{2}\right)\) would result from the breakup of the compound \(\mathrm{Cl}_{2} \mathrm{O}_{7} ?\) (1) \(1: 1\) (2) \(7: 2\) (3) \(1: 3.5\) (4) \(2: 4\)
Problem 84
The reaction \(2 \mathrm{C}+\mathrm{O}_{2} \longrightarrow 2 \mathrm{CO}\) is carried out by taking \(24 \mathrm{~g}\) of carbon and \(96 \mathrm{~g}\) of \(\mathrm{O}_{2}\). Which one is the limiting reagent? (1) \(\mathrm{C}\) (2) \(\mathrm{O}_{2}\) (3) \(\mathrm{CO}_{2}\) (4) Nonc
Problem 85
For the reaction \(\mathrm{A}+2 \mathrm{~B} \longrightarrow \mathrm{C}, 5\) moles of \(\mathrm{A}\) and 8 moles of B will produce (1) 5 moles of \(\mathrm{C}\) (2) 4 moles of \(\mathrm{C}\) (3) 8 moles of \(\mathrm{C}\) (4) 13 moles of \(\mathrm{C}\)
Problem 87
Element \(\Lambda\) (atomic weight \(12.01)\) and element \(\mathrm{B}\) (atomic weight 16 ) combine to form a new substance \(\mathrm{X}\). If two moles of \(\mathrm{B}\) combines with one mole of \(\Lambda\), then the weight of one mole of \(\mathrm{X}\) is (1) \(28.01 \mathrm{~g}\) (2) \(44.01 \mathrm{~g}\) (3) \(40.02 \mathrm{~g}\) (4) \(56.02 \mathrm{~g}\)
Problem 88
A mixture of \(20 \mathrm{ml}\) of methane and \(20 \mathrm{ml}\) of \(\mathrm{O}_{2}\) is exploded and cooled to room temperature. If the reaction between the two substances is written as $$ \mathrm{CH}_{4}+2 \mathrm{O}_{2} \longrightarrow \mathrm{CO}_{2}+2 \mathrm{H}_{2} \mathrm{O} $$ then the final volume of the gaseous mixture is (1) \(10 \mathrm{ml}\) (2) \(20 \mathrm{ml}\) (3) \(30 \mathrm{ml}\) (4) \(60 \mathrm{ml}\)
Problem 91
\(10 \mathrm{~g}\) of carbon burns giving \(11.2\) litres of \(\mathrm{CO}_{2}\) at NTP. After combustion, the amount of unburnt carbon is (1) \(2.5 \mathrm{~g}\) (2) \(4 \mathrm{~g}\) (3) \(3 \mathrm{~g}\) (4) \(1 \mathrm{~g}\)
Problem 92
The weight of \(\mathrm{MnO}_{2}\) required to produce \(1.78\) litres of chlorine gas at STP according to the reaction \(\mathrm{MnO}_{2}+4 \mathrm{HCl} \longrightarrow \mathrm{MnCl}_{2}+2 \mathrm{H}_{2} \mathrm{O}+\mathrm{Cl}_{2} \mathrm{is}\) (1) \(6.905 \mathrm{~g}\) (2) \(5.905 \mathrm{~g}\) (3) \(6.509 \mathrm{~g}\) (4) \(6.059 \mathrm{~g}\)
Problem 94
Chlorophyll contains \(2.68 \%\) of magnesium. The number of magnesium atoms present in 2 g of chlorophyll is (1) \(1.34 \times 10^{21}\) (2) \(6 \times 10^{20}\) (3) \(5.34 \times 10^{22}\) (4) \(5.34 \times 10^{23}\)
Problem 95
\(100 \mathrm{ml}\) of \(0.2 \mathrm{M} \mathrm{K}_{2} \mathrm{SO}_{4}\) is diluted with \(100 \mathrm{ml}\) of water. The \(\mathrm{K}^{+}\) ion in the solution (1) \(0.4 \mathrm{M}\) (2) \(0.1 \mathrm{M}\) (3) \(0.2 \mathrm{M}\) (4) \(0.8 \mathrm{M}\)
