Chapter 1

The number of significant figures for the numbers \(161 \mathrm{~cm}, 0.161 \mathrm{~cm}, 0.0161 \mathrm{~cm}\) are (a) 2,3 and 4 respectively (b) 3,3 and 3 respectively (c) 3,5 and 4 respectively (d) 3,4 and 4 respectively

What is the mass of \(0.5\) moles of \(\mathrm{O}_{3}\) molecules? (a) \(16 \mathrm{gm}\) (b) \(20 \mathrm{gm}\) (c) \(40 \mathrm{gm}\) (d) \(24 \mathrm{gm}\)

Which has maximum number of oxygen atoms? (a) \(1 \mathrm{gm}\) of \(\mathrm{O}\) (b) \(1 \mathrm{gm}\) of \(\mathrm{O}_{2}\) (c) \(1 \mathrm{gm}\) of \(\mathrm{O}_{3}\) (d) All have same no.of O-atoms

A mole of any substance is related to (a) number of particles (b) volume of gaseous substances (c) mass of a substance (d) all of these

What is the weight of oxygen required for the complete combustion of \(2.8 \mathrm{~kg}\) of ethylene? (a) \(9.6 \mathrm{~kg}\) (b) \(6.9 \mathrm{~kg}\) (c) \(96 \mathrm{~kg}\) (d) \(6.8 \mathrm{~kg}\)

The number of gram molecules of oxygen in \(6.02 \times\) \(10^{24} \mathrm{CO}\) molecules is (a) 1 gm molecules (b) 2 gm molecules (c) 5 gm molecules (d) 8 gm molecules

The number of oxygen atoms in \(4.4 \mathrm{~g}\) of \(\mathrm{CO}_{2}\) is (a) \(6 \times 10^{23}\) (b) \(11 \times 10^{23}\) (c) \(12 \times 10^{23}\) (d) \(1.2 \times 10^{23}\)

Boron has two stable isotopes, \(\mathrm{B}^{10}(19 \%)\) and \(\mathrm{B}^{11}\) (18\%) Find the average atomic weight of boron. (a) \(11.2\) (b) \(10.8\) (c) \(12.6\) (d) \(9.6\)

The number of moles of \(\mathrm{KCl}\) in \(1000 \mathrm{~mL}\) of 3 molar solution is (a) 2 (b) 3 (c) 4 (d) 6

The correct relationship between molecular mass and vapour density is (a) V.D. \(=2 \mathrm{M}\) (b) V.D. \(=\frac{\mathrm{M}}{2}\) (c) \(\mathrm{M}=(\mathrm{V} \cdot \mathrm{D} .)^{\frac{1}{2}}\) (d) \(\mathrm{VD}=\mathrm{M}^{2}\)

A bivalent metal has an equivalent mass of 32 , the molecular mass of metal nitrate is? (a) 168 (b) 182 (c) 184 (d) 188

How many moles of potassium chlorate should be decomposed completely to obtain \(67.2\) litres of oxygen at STP? (a) 1 (b) 2 (c) 3 (d) 4

The hydrated salt \(\mathrm{Na}_{2} \mathrm{CO}_{3} \cdot \mathrm{n} \mathrm{H}_{2} \mathrm{O}\) undergoes \(63 \%\) loss in mass on heating and becomes anhydrous. The value of \(n\) is (a) 4 (b) 6 (c) 8 (d) 10

The vapour density of a mixture having \(\mathrm{NO}_{2}\) and \(\mathrm{N}_{2} \mathrm{O}_{4}\) is \(27.6 .\) The mole fraction \(\mathrm{NO}_{2}\) in the mixture is (a) \(1.6\) (b) \(0.8\) (c) \(2.4\) (d) \(0.6\)

Among the following pairs of compounds, the one that illustrates the law of multiple proportions is (a) \(\mathrm{Cu}\) and \(\mathrm{CuSO}_{4}\) (b) \(\mathrm{CuO}\) and \(\mathrm{Cu}_{2} \mathrm{O}\) (c) \(\mathrm{H}_{2} \mathrm{~S}\) and \(\mathrm{SO}_{2}\) (d) \(\mathrm{NH}_{3}\) and \(\mathrm{NCl}_{3}\)

How many grams of \(\mathrm{KCl}\) must be added to \(75 \mathrm{~g}\) of water to produce a solution with a molality of \(2.25\) (a) \(1.257 \mathrm{~g}\) (b) \(125.7 \mathrm{~g}\) (c) \(12.57 \mathrm{~g}\) (d) \(25.14 \mathrm{~g}\)

Normality of \(0.04 \mathrm{M} \mathrm{H}_{2} \mathrm{SO}_{4}\) is (a) \(0.02 \mathrm{~N}\) (b) \(0.01 \mathrm{~N}\) (c) \(0.04 \mathrm{~N}\) (d) \(0.08 \mathrm{~N}\)

Which among the following is the heaviest? (a) one mole of oxygen (b) one molecule of sulphur trioxide (c) 100 amu of uranium (d) \(44 \mathrm{~g}\) of carbon dioxide

The molarity of pure water is (a) \(55.56 \mathrm{M}\) (b) \(5.56 \mathrm{M}\) (c) \(1.0 \mathrm{M}\) (d) \(0.01 \mathrm{M}\)

The number of grams of a dibasic acid (molecular weight 200 ) present is \(100 \mathrm{~mL}\) of its aqueous solution to give decinormal strength is (a) \(1 \mathrm{~g}\) (b) \(2 \mathrm{~g}\) (c) \(3 \mathrm{~g}\) (d) \(4 \mathrm{~g}\)

Normality of \(0.3 \mathrm{M} \mathrm{H}_{3} \mathrm{PO}_{4}\) solution is (a) \(0.1 \mathrm{~N}\) (b) \(0.45 \mathrm{~N}\) (c) \(0.6 \mathrm{~N}\) (d) \(0.9 \mathrm{~N}\)

7.5 gram of a gas occupies \(5.6\) litres as STP. The gas is (a) \(\mathrm{CO}\) (b) NO (c) \(\mathrm{CO}_{2}\) (d) \(\mathrm{N}_{2} \mathrm{O}\)

At STP the density of a gas (mol. wt = 45) in g/L is (a) \(11.2\) (b) 1000 (c) 2 (d) 224

How many moles of acidified \(\mathrm{FeSO}_{4}\) can be completely oxidized by one mole of \(\mathrm{KMnO}_{4}\) ? (a) 20 (b) 10 (c) 5 (d) \(0.5\)

A compound possess \(8 \%\) sulphur by mass. The least molecular mass is (a) 200 (b) 400 (c) 155 (d) 355

The vapour density of ozone is (a) 24 (b) 16 (c) 48 (d) 72

\(1000 \mathrm{~g}\) calcium carbonate solution contains \(10 \mathrm{~g}\) carbonate. The concentration of solution is (a) \(10 \mathrm{ppm}\) (b) \(100 \mathrm{ppm}\) (c) \(1000 \mathrm{ppm}\) (d) \(10,000 \mathrm{ppm}\)

One mole of \(\mathrm{CH}_{4}\) contains (a) \(4.0 \mathrm{~g}\) atoms of hydrogen (b) \(3.0 \mathrm{~g}\) atom of carbon (c) \(6.02 \times 10^{23}\) atoms of hydrogen (d) \(1.81 \times 10^{23}\) molecules of \(\mathrm{CH}_{4}\)

The maximum number of molecules is present in (a) \(15 \mathrm{~L}\) of \(\mathrm{H}_{2}\) gas at STP (b) \(5 \mathrm{~L}\) of \(\mathrm{N}_{2}\) gas at STP (c) \(1.5 \mathrm{~g}\) of \(\mathrm{H}_{2}\) gas (d) \(5 \mathrm{~g}\) of \(\mathrm{O}_{2}\) gas

The incorrect statement for \(14 \mathrm{~g}\) of \(\mathrm{CO}\) is (a) it occupies \(2.24\) litre at NTP (b) it corresponds to \(0.5 \mathrm{~mol}\) of \(\mathrm{CO}\) (c) it corresponds to same mol of \(\mathrm{CO}\) and \(\mathrm{N}_{2}\) (d) it corresponds to \(3.01 \times 10^{23}\) molecules of \(\mathrm{CO}\)

Area of nuclear cross section is measured in 'Barn'. It is equal to (a) \(10^{-28} \mathrm{~m}^{2}\) (b) \(10^{-18} \mathrm{~m}^{2}\) (c) \(10^{-8} \mathrm{~m}^{2}\) (d) \(10^{-34} \mathrm{~m}^{2}\)

Which of the following statement is correct? (a) 1 mole of electrons weighs \(5.4 \mathrm{mg}\) (b) 1 mole of electrons weighs \(5.4 \mathrm{~kg}\) (c) 1 mole of electrons weighs \(0.54 \mathrm{mg}\) (d) 1 mole of electrons has \(1.6 \times 10^{-19} \mathrm{C}\) of charge

Which of the following pairs of gases contain equal number of molecules? (a) \(\mathrm{CO}_{2}\) and \(\mathrm{NO}_{2}\) (b) \(\mathrm{CO}\) and \((\mathrm{CN})_{2}\) (c) \(\mathrm{NO}\) and \(\mathrm{CO}\) (d) \(\mathrm{N}_{2} \mathrm{O}\) and \(\mathrm{CO}_{2}\)

The samples of \(\mathrm{NaCl}\) are produced when Na combines separately with two isotopes of chlorine \(\mathrm{Cl}^{35}\) and \(\mathrm{Cl}^{57}\). Which law is illustrated? (a) Law of constant volume (b) Law of multiple proportions (c) Law of reciprocal proportions (d) None of these

Which of the following is the odd one with regard to mass? (a) \(1 \mathrm{~g}\) atom of sulphur (b) \(0.5\) moles of \(\mathrm{CO}_{2}\) (c) 1 mole of \(\mathrm{O}_{2}\) (d) \(3 \times 10^{23}\) molecules of \(\mathrm{SO}_{2}\)

A breakfast cereal in advertised to contain \(110 \mathrm{mg}\) of sodium per \(100 \mathrm{~g}\) of the cereal. The per cent of sodium in the cereal is (a) \(0.110 \%\) (b) \(0.0110 \%\) (c) \(11.0 \%\) (d) \(0.22 \%\)

The number of significant figures in \(306.45\) and 40440 are respectively (a) 4,5 (b) 5,5 (c) 5,4 (d) 4,6

The quantity of \(\frac{\mathrm{PV}}{\mathrm{K}_{\mathrm{B}} \mathrm{T}}\) represents the (a) molar mass of a gas (b) number of molecules in a gas (c) mass of gas (d) number of moles of a gas

Which is the correct order of micro, nano, femto and pico here? (a) micro \(<\) nano \(<\) pico \(<\) femto (b) pico \(<\) femto \(<\) nano \(<\) micro (c) femto \(<\) pico \(<\) nano \(<\) micro (d) femto \(<\) nano \(<\) micro \(<\) pico

15 litre atmosphere is equal to (a) \(1.515 \times 10^{8} \mathrm{erg}\) (b) \(15.15 \times 10^{9} \mathrm{erg}\) (c) \(1.515 \times 10^{10} \mathrm{erg}\) (d) \(15.15 \times 10^{12} \mathrm{erg}\)

Mixture \(\mathrm{X}=0.02 \mathrm{~mol}\) of \(\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{SO}_{4}\right] \mathrm{Br}\) and \(\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Br}\right] \mathrm{SO}_{4}\) was prepared in 2 litre of solution. 1 litre of mixture \(\mathrm{X}+\mathrm{excess} \mathrm{AgNO}_{3} \longrightarrow \mathrm{Y}\) 1 litre of mixture \(\mathrm{X}+\) excess \(\mathrm{BaCl}_{2} \longrightarrow \mathrm{Z}\) Number of moles of \(Y\) and \(Z\) are (a) \(0.02,0.01\) (b) \(0.01,0.01\) (c) \(0.01,0.02\) (d) \(0.02,0.02\)

The amount of zinc required to produce \(224 \mathrm{~mL}\) of \(\mathrm{H}_{2}\) at STP on treatment with dilute \(\mathrm{H}_{2} \mathrm{SO}_{4}\) will be \((\mathrm{Zn}=65)\) (a) \(65.0 \mathrm{~g}\) (b) \(0.65 \mathrm{~g}\) (c) \(6.35 \mathrm{~g}\) (d) \(0.065 \mathrm{~g}\)

Ratio of \(\mathrm{C}_{\mathrm{p}}\) and \(\mathrm{C}_{\mathrm{v}}\) of a gas ' \(\mathrm{X}\) ' is \(1.4\). The number of atoms of the gas 'X' present in \(11.2\) litres of it at NTP will be (a) \(6.02 \times 10^{21}\) (b) \(60.2 \times 10^{23}\) (c) \(6.02 \times 10^{23}\) (d) \(1.02 \times 10^{23}\)

When \(18 \mathrm{~g}\) of glucose is dissolved in \(180 \mathrm{~g}\) of water then the mole fraction of glucose is (a) \(0.0099\) (b) \(0.0999\) (c) \(0.9999\) (d) \(0.9111\)

The weight of \(1 \times 10^{22}\) molecules of \(\mathrm{CuSO}_{4} \cdot 2 \mathrm{H}_{2} \mathrm{O}\) is (a) \(42.42 \mathrm{~g}\) (b) \(41.42 \mathrm{~g}\) (c) \(44.44 \mathrm{~g}\) (d) \(48.94 \mathrm{~g}\)

If \(\mathrm{N}_{\mathrm{A}}\) is Avogadro's number then number of valence electrons in \(4.2 \mathrm{~g}\) of nitride ions \(\left(\mathrm{N}^{3}\right)\) is (a) \(3.2 \mathrm{~N}_{\mathrm{A}}\) (b) \(1.6 \mathrm{~N}_{\mathrm{A}}\) (c) \(2.4 \mathrm{~N}_{\mathrm{A}}\) (d) \(1.2 \mathrm{~N}_{\mathrm{A}}\)

In the final answer of the expression $$ \frac{(29.2-20.2)\left(1.79 \times 10^{5}\right)}{1.37} $$ The number of significant figures is (a) 2 (b) 4 (c) 6 (d) 7

The number of moles of oxygen in one litre of air containing \(21 \%\) oxygen by volume, in standard conditions, is (a) \(0.176 \mathrm{~mol}\) (b) \(0.32 \mathrm{~mol}\) (c) \(0.0093 \mathrm{~mol}\) (d) \(2.20 \mathrm{~mol}\)

Number of atoms in \(4.25 \mathrm{~g}\) of \(\mathrm{NH}_{3}\) is approximately (a) \(6 \times 10^{23}\) (b) \(15 \times 10^{23}\) (c) \(1.5 \times 10^{23}\) (d) \(2.5 \times 10^{23}\)

The percentage weight of \(\mathrm{Zn}\) in white vitriol \(\left[\mathrm{ZnSO}_{4} \cdot 7 \mathrm{H}_{2} \mathrm{O}\right]\) is approximately equal to \((\mathrm{Zn}=65\), \(\mathrm{S}=32, \mathrm{O}=16\) and \(\mathrm{H}=1\) ) (a) \(21.56 \%\) (b) \(32.58 \%\) (c) \(22.65 \%\) (d) \(26.55 \%\)