Chapter 1

Out of molarity \((F)\), molality \((m)\), formality \((F)\) and mole fraction \((x)\), those independent of temperature are (a) \(M, m\) (b) \(\bar{F}, x\) (c) \(m, x\) (d) \(M x\)

\(X\) and \(Y\) are two elements which form \(X_{2} Y_{3}\) and \(X_{3} Y_{4}\). If \(0.20\) mol of \(X_{2} Y_{3}\) weighs \(32.0 \mathrm{~g}\) and \(0.4\) mol of \(X_{3} Y_{4}\) weighs \(92.8 \mathrm{~g}\), the atomic weighs of \(X\) and \(Y\) are respectively (a) \(16.0\) and \(56.0\) (b) \(8.0\) and \(28.0\) (c) \(56.0\) and \(16.0\) (d) \(28.0\) and \(8.0\)

The equivalent weight of an element is 4 . Its chloride has a vapor density of \(59.25\). Then the valency of the element is (a) 4 (b) 3 (c) 2 (d) 1

A metal oxide has \(40 \%\) oxygen. The equivalent weight of the metal is (a) 12 (b) 16 (c) 24 (d) 48

An oxide of iodine \((1=127)\) contains \(25.4 \mathrm{~g}\) of iodine for \(8 \mathrm{~g}\) of oxygen. lis formula could be (a) \(10_{23}\) (b) \(1.0\) (c) \(_{2} \mathrm{O}_{5}\) (d) \(1_{2} \mathrm{O}_{7}\)

About \(1.60 \mathrm{~g}\) of a metal was dissolved in \(\mathrm{HNO}_{3}\) to prepare its nitrate. The nitrate on strong heating gives \(2 \mathrm{~g}\) oxide. The equivalent weight of metal is (a) 16 (b) 32 (c) 48 (d) 12 ?

When \(1 \mathrm{~L}\) of \(\mathrm{CO}_{2}\) is heated with graphite, the volume of the gases collected is \(1.5 \mathrm{~L}\). Calculate the number of moles of CO produced at STP. (a) \(1 / 11.2\) (b) \(28 / 22.4\) (c) \(1 / 22.4\) (d) \(14 / 22.4\)

A \(0.242 \mathrm{~g}\) sample of potassium is heated in oxygen. The result is \(0.440 \mathrm{~g}\) of a crystalline compound. What is the formula of this compound? (a) \(\mathrm{KO}\) (b) \(\mathrm{K}_{2} \mathrm{O}\) (c) \(\mathrm{KO}_{2}\) (d) \(\mathrm{KO}_{3}\)

For the reaction \(A+2 B \rightarrow C, 5\) moles of \(A\) and 8 moles of \(B\) will produce (a) 5 moles of \(\bar{C}\) (b) 4 moles of \(\vec{C}\) (c) 8 moles of \(\mathrm{C}\) (d) 13 moles of \(C\)

The density in grams per litre of a mixture containing an equal number of moles of methane and ethane at STP is (a) \(1.03\) (b) \(1.10\) (c) \(0.94\) (d) \(1.20\)

In the following reaction $$ 2 \mathrm{H}_{2} \mathrm{~S}+\mathrm{SO}_{2} \rightarrow 2 \mathrm{H}_{2} \mathrm{O}+3 \mathrm{~S} $$ 1\. mol each of \(\mathrm{SO}_{2}\) and \(\mathrm{H}_{2} \mathrm{~S}\) will give sulphur (a) \(1 \mathrm{~mol}\) (b) \(3 \mathrm{~mol}\) (c) \(1.5 \mathrm{~mol}\) (d) \(2 \mathrm{~mol}\)

The percent loss in weight after heating a pure sample of potassium chlorate (mol. wt. = 122.5) will be (a) \(12.25\) (b) \(24.50\) (c) \(39.18\) (d) \(49.0\)

A certain compound has the molecular formula \(\mathrm{X}_{4} \mathrm{O}_{6}\). If \(10 \mathrm{~g}\) of \(\mathrm{X}_{4} \mathrm{O}_{6}\) has \(5.72 \mathrm{~g} \mathrm{X}\), then the atomic mass of \(\mathrm{X}\) is (a) \(32 \mathrm{amu}\) (b) 37 amu (c) 42 amu (d) \(98 \mathrm{amu}\)

The decomposition of a certain mass of \(\mathrm{CaCO}_{3}\) gave \(11.2 \mathrm{dm}^{-3}\) of \(\mathrm{CO}_{2}\) gas at STP. The mass of \(\mathrm{KOH}\) required to completely neutralize the gas is (a) \(56 \mathrm{~g}\) (b) \(28 \mathrm{~g}\) (c) \(42 \mathrm{~g}\) (d) \(20 \mathrm{~g}\)

The specific heat of a metal is \(0.16\), its approximate atomic weight would be (a) 32 (b) 16 (c) 40 (d) 64

An element \(X\) has the following isotopic composition \({ }^{200} \mathrm{X}=90 \%,{ }^{199} \mathrm{X}=8 \%,{ }^{202} \mathrm{X}=2 \%\) The weighed average atomic mass of the naturally occurring element ' \(X^{\prime}\) is closest to (a) \(201 \mathrm{amu}\) (b) 202 amus (e) 109 amu (d) 200 amu

If \(30 \mathrm{~mL}\) of \(\mathrm{H}_{2}\) and \(20 \mathrm{~mL}\) of \(\mathrm{O}_{2}\) react to form water. What is left at the end of the reaction? (a) \(10 \mathrm{~mL}\) of \(\mathrm{H}_{2}\) (b) \(5 \mathrm{~mL}\) of \(\mathrm{H}_{2}\) (c) \(10 \mathrm{~mL}\) of \(\mathrm{O}_{2}\) (d) \(5 \mathrm{~mL}\) of \(\mathrm{O}_{2}\)

A.gas is found to have the formula (CO) \(_{x}\). Its V.D. is 70 . The value of \(x\) must be (a) 7 (b) 4 (c) 5 (d) 6

Which of the following has the highest number of atoms ? (a) \(7.5 \mathrm{~mol}\) of \(\mathrm{H}_{2} \mathrm{O}\) (b) \(250 \mathrm{~g}\) of \(\mathrm{H}_{2} \mathrm{SO}_{5}\) (c) \(200 \mathrm{ml} \mathrm{O}_{3}\) at NTP (d) \(1.5 \mathrm{~mol}\) of \(\mathrm{OsO}_{4}\)

Haemoglobin contains \(0.33 \%\) of iron by weight. The molecular weight of haemoglobin is approximately \(67200 .\) The number of iron atoms (at. wt. of \(\mathrm{Fe}=56\) ) present in one molecule of haemoglobin is (9) 6 (b) 1 (c) 4 (d) 2

An aqueous solution of \(6.3 \mathrm{~g}\) of oxalic acid dihydrate is made up to \(250 \mathrm{~mL}\). The volume of \(0.1 \mathrm{~N} \mathrm{NaOH}\) required to completely neutralize \(10 \mathrm{~mL}\) of this solution is (a) \(40 \mathrm{~mL}\) (b) \(20 \mathrm{~mL}\) (c) \(10 \mathrm{~mL}\) (d) \(4 \mathrm{~mL}\)

If \(0.5\) mole of \(\mathrm{BaCl}_{2}\) is mixed with \(0.20\) mole of \(\mathrm{Na}_{3} \mathrm{PO}_{4}\), the maximum number of \(\mathrm{Ba}_{3}\left(\mathrm{PO}_{4}\right)_{2}\) that can be formed is (a) \(0.70\) (b) \(0.50\) (c) \(0.20\) (d) \(0.10\)

The percentage of \(\mathrm{P}_{2} \mathrm{O}_{5}\) in diammonium hydrogen phosphate \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{HPO}_{4}\) is (a) \(23.48\) (b) \(46.96\) (c) \(53.78\) (d) \(71.00\)

The equivalent weight of phosphoric acid \(\mathrm{H}_{3} \mathrm{PO}_{4}\) in the reaction \(\mathrm{NaOH}+\mathrm{H}_{3} \mathrm{PO}_{4} \rightarrow \mathrm{NaH}_{2} \mathrm{PO}_{4}+\mathrm{H}_{2} \mathrm{O}\) is (a) 59 (b) 49 (c) 25 (d) 98

A \(3 \mathrm{~g}\) of oxide of a metal is converted to chloride completely and it yields \(5 \mathrm{~g}\) of chloride. The equivalent weight of the metal is (a) \(33.25\) (b) \(3.325\) (c) 12 (d) 20

A \(3.54 \mathrm{~g}\) of an oxide of lead contains \(3.22 \mathrm{~g}\) of lead. Identify the formula of this oxide from the following (a) \(\mathrm{PbO}_{2}\) (b) \(\mathrm{PbO}\) (c) \(\mathrm{Pb}_{3} \mathrm{O}_{4}\) (d) None of these