Single Choice

0.0852 g of an organic halide (A) when dissolved in 2.0 g of camphor, the melting point of the mixture was found to be $$167^{\circ}$$C. Compound (A) when heated with sodium gives a gas (B). 280 mL of gas (B) at STP weighs 0.375g. What would be 'A' in the whole process? $$K_f$$ for camphor = 40, m.pt. of camphor = $$179^{\circ}$$C.

A$$C_2H_5Br$$
B$$CH_3I$$
Correct Answer
C$$(CH_3)_2CHI$$
D$$C_3H_7Br$$

Solution

$$\delta$$=179-167=12, w=0.0852g, W=2g,Kf= 40 Moleculer weight of (A) =$$\dfrac{1000\times{Kf}\times{w} }{\delta{T}\times {W}}$$ =$$\dfrac{1000\times{40}\times{0.0852} }{\delta{12}\times {2}}$$ =142 (A) undergoes wortz reaction to form (B) i.e $$(A)\rightarrow{Na} (B)+NaX$$ (B) is an alkane say $$C_nH_2n+2$$ $$\therefore$$ 280 mL of (B) weighs 0.375 g at NTP $$\therefore$$ 22400 mL of (B) weighs =$$\dfrac{0.375\times{22400}}{280}$$ =30 g at NTP M.wt of (B)=30, 12n+2n+2=30,n=2 Thus (B) is ethane and therefore (A) is $$CH_3X$$ The m.wt of $$CH_3X$$=142 At.wt of X=127 $$\therefore$$ is iodine Therefore alkyl halide is $$CH_3I$$. This reaction is 2$$CH_3I\xrightarrow[Na]{ether} C_2h_6$$ (A) (B)

SIMILAR QUESTIONS

Solutions

A compound $$MX_{2}$$ has observed and normal molar masses 65.6 and 164 respectively. The apparent degree of ionization of $$MX_{2}$$ is:

Solutions

A weak electrolyte $$(AB_2)$$ with formula mass 100 g / mole is dissociated in water upto 50%. The observed molar mass of the electrolyte is:

Solutions

The molecular weight of benzoic acid in benzene as determined by depression in the freezing point method corresponds to:

Solutions

When a liquid that is immiscible with water was steam distilled at $${\text{95}}{\text{.}}{{\text{2}}^{\text{o}}}{\text{C}}$$ at a total pressure of 748 torr, the distillate contained 1.25 g of the liquid per gram of water. The vapour pressure of water is 648 torr at $${\text{95}}{\text{.}}{{\text{2}}^{\text{o}}}{\text{C}}$$, What is the molar mass of liquid?

Solutions

Acetic acid dissolved in benzene shows a molecular weight of:

Solutions

Benzoic acid dissolved in benzene will show a molecular mass of:

Solutions

Boiling point of chloroform was raised by $$0.323 K$$, when $$0.5143 g$$ of anthracene was dissolved in $$35 g$$ of chloroform. Molecular mass of anthracene is $$\left( {{K_b}\,for\,CHC{l_3} = 3.9\,K\,\,kg\,mo{l^{ - 1}}} \right)$$

Solutions

If the observed and theoretical molecular mass of NaCl is found to be 31.80 and 58.50, then the degree of dissociation of NaCl is:

Solutions

Molecules of ethanoic acid dimerises in benzene due to $$H-$$bonding if all molecules of ethanoic acid associated in benzene then:

Contact Details