Chapter 17

In organic chemistry, the clement which is estimated by difference is (a) \(\mathrm{N}\) (b) \(\mathrm{O}\) (c) \(\mathrm{S}\) (d) \(\mathrm{H}\)

An organic compound is fused with fusion mixture and extracted with \(\mathrm{HNO}_{3}\). The extract gives yellow precipitate with ammonium molybdate. It shows the presence of which clement? (a) \(\mathrm{P}\) (b) As (c) Both \(\mathrm{P}\) and \(\mathrm{As}\) (d) May be \(\mathrm{P}\) or \(\mathrm{As}\) or Both

The percentage of bromine (by weight) in ethyl bromide is approximately (a) \(80 \%\) (b) \(74 \%\) (c) \(70 \%\) (d) \(7 \%\)

The constituents of a mixture of acetone and methanol can be separated by (a) steam distillation (b) vacuum distillation (c) fractional distillation (d) crystallization

About \(15 \mathrm{~mL}\) of a gaseous hydrocarbon requires \(45 \mathrm{~mL}\) of oxygen for complete combustion, which produces \(30 \mathrm{~mL}\) of \(\mathrm{CO}_{2}\) gas. The formula of the hydrocarbon is (a) \(\mathrm{C}_{3} \mathrm{H}_{6}\) (b) \(\mathrm{C}_{2} \mathrm{H}_{6}\) (c) \(\mathrm{C}_{4} \mathrm{H}_{10}\) (d) \(\mathrm{C}_{2} \mathrm{H}_{4}\)

Aniline is sparingly soluble in water and possesses low vapour pressure, it is best purified by (a) vacuum distillation (b) simple distillation (c) fractional distillation (d) steam distillation

About \(20 \mathrm{~mL}\) of \(\mathrm{CH}_{4}\) is burnt with \(60 \mathrm{~mL}\) of \(\mathrm{O}_{2}\). If all measurements are made at the same Pand \(T\), what is the volume of unreacted oxygen? (a) \(10 \mathrm{~mL}\) (b) \(20 \mathrm{ml}\). (c) \(30 \mathrm{~mL}\) (d) \(40 \mathrm{~mL}\).

Turpentine oil can be best purified by (a) steam distillation (b) simple distillation (c) vacuum distillation (d) fractional distillation

About \(0.14 \mathrm{~g}\) of an acid requires \(12.5 \mathrm{~mL}\) of \(0.1 \mathrm{~N}-\mathrm{NaOH}\) for complete neutralization. The equivalent weight of the acid is (a) 45 (b) 56 (c) 63 (d) 112

About \(0.5 \mathrm{~g}\) of an organic compound containing nitrogen on \(\mathrm{Kjeldahlising}\) requires \(29 \mathrm{~mL}\) of N/5 \(\mathrm{H}_{2} \mathrm{SO}_{4}\) for complete neutralization of ammonia. The percentage of nitrogen in the compound is (a) \(34.3 \%\) (b) \(16.2 \%\) (c) \(21.6 \%\) (d) \(14.8 \%\)

In sodium fusion test of organic compounds, the nitrogen of an organie compound is converted into (a) sodium amide (b) sodium cyanide (c) sodium nitrite (d) sodium nitrate

About \(15 \mathrm{~mL}\) of a gaseous hydrocarbon required \(45 \mathrm{~mL}\) of oxygen for complete combus: tion: \(30 \mathrm{~mL}\), of \(\mathrm{CO}_{2}\) is formed. The formula of the hydrocarbon is (a) \(\mathrm{C} \mathrm{H}_{6}\) (b) \(\mathrm{C}_{3} \mathrm{H}_{6}\) (c) \(\mathrm{C}_{2} \mathrm{H}_{4}\) (d) \(\mathrm{C}_{2} \mathrm{H}_{2}\)

Beilstein's test is given by which of the following? (a) Halogens (b) Thiourea (c) Pyridine (d) All

chiff's and Piria's method is used for the estimation of as) nitrogen (b) sulphur (c) halogens (d) oxygen

The empirical formula of a compound is \(\mathrm{CH}_{2}\). One mole of the compound has a mass of \(42 \mathrm{~g}\). Its molecular formula is (a) \(\mathrm{CH}_{2}\) (b) \(\mathrm{C}_{2} \mathrm{H}_{2}\) (c) \(\mathrm{C}_{3} \mathrm{H}_{6}\) (d) \(\mathrm{C}_{3} \mathrm{H}_{8}\)

About \(0.365 \mathrm{~g}\) of an organic compound containing nitrogen gave \(56 \mathrm{~mL}\) of nitrogen at S.T.P, the percentage nitrogen in the given compound is (a) \(19.18 \%\) (b) \(38.36 \%\) (c) \(9.18 \%\) (d) \(29.18 \%\)

The most suitable method of separation of \(1: 1\) mixture of ortho and para nitrophenols is (a) distillation (b) crystallization (c) sublimation (d) chromatography

If \(0.2 \mathrm{~g}\) of an organic compound containing carbon, hydrogen and oxygen on combustion, yielded \(0.147 \mathrm{~g}\) of carbon dioxide and \(0.12 \mathrm{~g}\) of water, what will be the content of oxygen in the substance? (a) \(73.29 \%\) (b) \(78.45 \%\) (c) \(83.23 \%\) (d) \(89.50 \%\)

An organic compound having molecular mass 60 is found to contain \(C=20 \%, H=6.67 \%\) and \(\mathrm{N}=46.67 \%\) while rest is oxygen. On heating it gives \(\mathrm{NH}_{3}\) along with a solid residue. The solid residue gives violet colour with alkaline copper sulphate solution. The compound is (a) \(\mathrm{CH}_{y} \mathrm{NCO}\) (b) \(\mathrm{CH}_{3} \mathrm{CONH}_{2}\) (c) \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{CO}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CONH}_{2}\)

The ammonia evolved from the treatment of \(0.30 \mathrm{~g}\) of an organic compound ror the estimation of nitrogen was passed in \(100 \mathrm{~mL}\) of \(0.1 \mathrm{M}\) sulphuric acid. The excess of acid required \(20 \mathrm{~mL}\) of \(0.5 \mathrm{M}\) sodium hydroxide solution for complete neutralization. The organic compound is (a) urea (b) thiourea (c) acetamide (d) benzamide

In a compound \(\mathrm{C}, \mathrm{H}\) and \(\mathrm{N}\) atoms are present in \(9: 1: 3.5\) by weight. If molecular weight of the compound is 108 , then molecular formula of the compound is (a) \(\mathrm{C}_{2} \mathrm{H}_{0} \mathrm{~N}_{2}\) (b) \(\mathrm{C}_{3} \mathrm{H}_{4} \mathrm{~N}\) (c) \(\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{~N}_{2}\) (d) \(\mathrm{C}_{9} \mathrm{H}_{12} \mathrm{~N}_{3}\)

Percentage of Se (at, wt, =78.4) in peroxidase anhydrase enzyme is \(0.5 \%\) by weight, then minimum molecular weight of peroxidase anhydrase enzyme is (a) \(1.568 \times 10^{4}\) (b) \(1.568 \times 10^{3}\) (c) \(15.68\) (d) \(2.136 \times 10^{4}\)

An organic compound has \(11.5 \%\) nitrogen. It is subjected to Kjeldahl's method and the ammonia evolved is absorbed in \(100 \mathrm{ml}\) of normal sulphuric acid. About \(400 \mathrm{ml}\) of water was added. And \(20 \mathrm{ml}\) of this new solution now required \(16 \mathrm{ml}\) of \(\mathrm{N} / 5 \mathrm{NaOH}\) for complete neutralization. Calculate the original weight of the organic compound taken. (a) \(2.432 \mathrm{~g}\) (b) \(3.156 \mathrm{~g}\) (c) \(4.058 \mathrm{~g}\) (d) \(1.850 \mathrm{~g}\)