Saturated and Unsaturated Hydrocarbons

Q.

How will you convert ethane to ethanol. Give the equation.

Q.

The order of stability of cyclohexane conformations is :

1. Chair > twist boat > boat > half chair

2. twist boat > chair > boat > half chair

3. boat > twist boat > chair > half chair

4. Chair > half chair > boat > twist boat

Q.

Which of the following fatty acids is saturated?

1. Oleic acid

2. Linoleic acid

3. Arachidonic acid

4. Palmitic acid

Q.

Give reasons :
(a) Ethyne is more reactive than ethene.
(b) Ethene is more reactive than ethane.
(c) Hydrocarbons are excellent fuels.

Q.

Which of the following hydrocarbons is unsaturated?
$C_3{H}_4;C_2{H}_6$

Q. What are saturated and unsaturated compounds? Give examples.

Q.

(a) What are hydrocarbons? Explain with examples.
(b) Explain the meaning of saturated and unsaturated hydrocarbons with two examples each.
(c) Give the names and structural formulae of one saturated cyclic hydrocarbon and one unsaturated cyclic hydrocarbon.
(d) Give one example of a hydrocarbon, other than pentane, having more than three isomers.
(e) How many isomers of the following hydrocarbons are possible?
(i) $C_3{H}_8$ (ii) $C_4{H}_{10}$ (iii) $C_5{H}_{12}$ (iv) $C_6{H}_{14}$

Q.

Alkenes as well as alkynes decolourise bromine water.

1. True

2. False

Q.

Which of the following will not decolourise bromine water?

1. 

2. 

3. 

4. 

Q. Why unsaturated hydrocarbons decolourise bromine ?

Q. Compounds with single bond are stable than those with double or triple bonds.

1. True
2. False

Q.

Which of the following represent the correct increasing order of unsaturation?

1. Alkanes < Alkenes < Alkynes

2. Alkanes < Alkynes < Alkenes

3. Alkenes < Alkynes < Alkenes

4. Alkynes < Alkanes < Alkenes

Q.

Which of the following compounds can have a triple bond?
$C_2{H}_4,C_3{H}_4,C_3{H}_6$

Q.

An unsaturated hydrocarbon having a triple covalent bond has 50 hydrogen atoms in its molecule. The number of carbon atoms in its molecule will be :
(a) 24 (b) 25 (c) 26 (d) 28

Q.

A saturated hydrocarbon has fifty hydrogen atoms in its molecule. The number of carbon atoms in its molecule will be :
(a) twenty five (b) twenty-four (c) twenty-six (d) twenty-seven

Q.

Question 48
(a) What are hydrocarbons? Give examples.
(b) Give the structural difference between saturated and unsaturated hydrocarbons with two examples of each.
(c) What is a functional group? Give examples of four different functional groups.

Q. The total number of hydrogen atoms present in two molecules of propyne is

1. $4$
2. $8$
3. $12$
4. $6$

Q.

One of the following contains a double bond as well as single bonds. This is:
(a) $C{O}_2$

(b) Methane

(c) Ethene

(d) Nitrogen

Q. Ethene $(H_{2}C=C{H}_2)$ is an unsaturated hydrocarbon.

1. True
2. False

Q.

Write the molecular formula of (i) an alkane (ii) an alkene, and (iii) an alkyne, each having 20 carbon atoms.

Q.

Alkanes are soluble in ________.

Q.

You are given the following molecular formulae of some hydrocarbons :
$C_5{H}_8$ , $C_7{H}_{14}$ , $C_6{H}_6$ , $C_5{H}_{10}$ , $C_7{H}_{12}$ , $C_6{H}_{12}$
(a) Which formula represents cyclohexane as well as hexene?
(b) Which formula represents benzene?
(c) Which three formulae represent open-chain unsaturated hydrocarbons having double bonds?
(d) Which two formulae represent unsaturated hydrocarbons having triple bonds?
(e) Which three formulae can represent cyclic hydrocarbons?

Q.

Classify the following compounds as alkanes, alkenes and alkynes : $C_3{H}_4,C_3{H}_8,C_5{H}_8,C_3{H}_6$

Q. A hydrocarbon has a molecular formula as $C_6{H}_{12}$. It does not react with hydrogen to give $C_6{H}_{14}$ nor does it react with chlorine to give $C_6{H}_{12}C{l}_2$. The hydrocarbon $C_6{H}_{12}$ is _____.

1. a saturated hydrocarbon
2. an unsaturated hydrocarbon
3. an open chain hydrocarbon
4. a cyclo-alkane.

1. (1) & (2)
2. (3) & (4)
3. (4) & (2)
4. (1) & (4)

Q.

Which of the following compounds can have a double bond?
$C_4{H}_{10};C_5{H}_8;C_5{H}_{10}$

Q.

Fill in the blanks with the correct words from the brackets :

Alkenes are the (a) ...... (analogous/homologous) series of (b) ... (saturated/unsaturated) hydrocarbons. They differ from alkanes due to the presence of (c) .... (double/single) bonds. Alkenes mainly undergo (d) (addition/ substitution) reactions.

Q.

(a) Give the general formula of an : (i) alkane (ii) alkene (iii) alkyne.
(b) Classify the following compounds as alkanes, alkenes and alkynes :
$C_2{H}_4,C_3{H}_4,C_4{H}_8,C_5{H}_{12},C_5{H}_8,C_3{H}_8,C_6{H}_6$

Q.

Which of the given compounds burn with a sooty flame? Naphthalene, Ethanol, Butane

Q.

Which of the folloiwng has a triple bond as well as single bonds?
(a) ethene

(b) methane

(c) ethyne

(d) nitrogen

Q. Ethanol can be converted to ethene which can then be changed to ethane.
Choose the correct word or phrase from the brackets to complete the following sentences:
(i) The conversion of ethanol to ethene is an example of ........... (dehydration, dehydrogenation).
(ii) Converting ethanol to ethene requires the use of ......... (concentrated hydrochloric acid, concentrated nitric acid, concentrated sulphuric acid).
(iii) The conversion of ethene to ethane is an example of ......... (hydration, hydrogenation).
(iv) The catalyst used in the conversion of ethene to ethane is commonly ............ (iron, cobalt, nickel).