Physical Properties of Alkynes

Q.

The polymer used as electrodes in batteries is

1. polythene

2. polypropene

3. polyacetylene

4. poly vinyl chloride

Q.

$Ca{C}_2\stackrel{H_{2}O}{\to }A\underset{N{H}_{4}OH}{\overset{C{u}_{2}C{l}_2}{\to }}B.$ Incorrect statement is

1. Pure form of 'A' has garlic smell

2. 'A' is used in Hawker's lamp and Holme's signal

3. 'B' is red ppt

4. Oxidation state of 'Cu' in Cu₂Cl₂ and 'B' is same

Q.

Solubilitity of alkynes in H₂O is more than their corresponding alkanes and alkenes - True or False?

1. True
2. False

Q.

The most volatile compound is

1. 2, 2-dimethyl propane

2. 2-methyl butane

3. Isobutane

4. n-pentane

Q. Solubilitity of alkynes in H₂O is more than their corresponding alkanes and alkenes.

1. True
2. False

Q. Which of the following improperly describes the physical property of an alkyne?

1. Relatively non-polar
2. Insoluble in alcohols and ethers
3. less dense than water
4. Nearly insoluble in water

Q. The correct order of C - H bond length in $C{H}_3-C{H}_3,C{H}_2=C{H}_2$ and $CH\equiv CH$ is:

1. $C{H}_3-C{H}_3<C{H}_2=C{H}_2<CH\equiv CH$
2. $C{H}_2=C{H}_2<C{H}_3-C{H}_3<CH\equiv CH$
3. $CH\equiv CH<C{H}_2=C{H}_2<C{H}_3-C{H}_3$
4. all are equal

Q. Choose the correct statment(s) for alkynes :

1. $\text{Boiling point}\propto \frac{1}{\text{Molar mass}}$
2. $\text{Melting point}\propto \text{Molar mass}$
3. Density of alkynes increases with the increase in their molar mass
4. $\text{Boiling point}\propto \frac{1}{\text{Van der Waals force}}$

Q. Choose the correct statement(s) regarding alkynes :

1. All alkynes are gases at room temperature.
2. Alkynes are colourless
3. Alkynes are highly polar in nature.
4. Except ethyne, alkynes are odourless.

Q. Alkynes are heavier than water.

1. True
2. False