Preparation and Properties of Compounds MCQ Questions & Answers in Inorganic Chemistry | Chemistry

$$\eqalign{ & Equiv.{\text{ mass of}}\,\,kMn{O_4} \cr & MnO_4^ - = \frac{{{\text{molar mass}}}}{{7 - 2}} \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{{\text{molar mass}}}}{5} \cr & Equiv.{\text{ mass of oxalic acid}} \cr & {C_2}O_4^{2 - } = \frac{{{\text{molar mass}}}}{{2\left( {4 - 3} \right)}} \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = \frac{{{\text{molar mass}}}}{2} \cr} $$
$$Meq.{\text{ of}}\,\,KMn{O_4} = 50 \times 5 \times 0.04$$       $$ = 10 = meq\,\,{\text{of }}{H_2}{C_2}{O_4} = $$      $$50 \times 2 \times 0.1 = 10.\,{\text{Hence}}\,\left( C \right).$$

Kjeldahl’s method depends upon the fact that most of the organic compounds containing nitrogen are quantitatively decomposed to give $${\left( {N{H_4}} \right)_2}S{O_4}$$   when heated strongly with $$conc.\,{H_2}S{O_4}.$$    In this method $$CuS{O_4}$$  acts as catalytic agent.

Beilstein's test: Organic compounds containing halogens when heated over $$Cu$$  wire loop give blue or green colour flame due to formation of volatile copper halides.

When the nitrogen containing compound is heated with sodium, then nitrogen and carbon of organic compound converted into sodium cyanide.
$$Na + \underbrace {C + N}_{{\text{From organic compound}}} \to NaCN$$

$$C{H_3}CHO;$$   differentiated by $$Na,$$  Fehling Tollen's test
\[\underset{\left( Q \right)}{\mathop{C{{H}_{3}}-C{{H}_{2}}-O-C{{H}_{2}}-C{{H}_{3}}}}\,\xrightarrow{{{H}_{3}}{{O}^{\oplus }}}EtOH\]

Table for empirical formula

Hence, empirical formula is $$C{H_4}N.$$

$$\eqalign{ & Eq.{\text{ of acid = }}Eq.{\text{ of base,}} \cr & \therefore \,\frac{{0.45}}{{E.wt}} = \frac{{20 \times 0.5}}{{1000}}, = E.wt = 45 \cr & {\text{Basicity}} = \frac{{M.wt}}{{E.wt}} = \frac{{90}}{{45}} = 2 \cr} $$

Aniline is miscible in steam and has $$b.p.$$  lower than water, hence it is collected as distillate along with steam.

$$28 \times x = 140 \Rightarrow x = 5$$

Among the given compounds naphthelene is volatile but benzoic acid is non-volatile ( it forms a dimer ). So, the best method for their separation is sublimation,