Question

7. Write a formula for each of the following:

(a) an alkane with 22 carbon atoms
(b) an alkene with 17 carbon atoms
(c) an alkyne with 13 carbon atoms.

Answer 1

`\huge \boxed{{C_(22) H_(46) \ \ \ \ C_(17) H_(34) \ \ \ \ C_(13) H_(24)}}`

Step-by-step explanation:

`alkanes \ \Rightarrow \ C_n H_(2n+2)`

`C_(22) H_(2(22)+2)`

`C_(22) H_(44+2)`

`C_(22) H_(46)`

`alkenes \ \Rightarrow \ C_n H_(2n)`

`C_(17) H_(2(17))`

`C_(17) H_(34)`

`alkynes \ \Rightarrow \ C_n H_(2n-2)`

`C_(13) H_(2(13)-2)`

`C_(13) H_(26-2)`

`C_(13) H_(24)`

Answer 2

Answer : The formula for each of the following is:

(a)
`C_(22)H_(46)`

(b)
`C_(17)H_(34)`

(c)
`C_(13)H_(24)`

Explanation :

• Alkanes are hydrocarbon in which the carbon atoms are connected with single covalent bonds.

The general formula of alkanes is
`C_n H_(2n+2)` where n is the number of the carbon atoms present in a molecule of alkane.

• Alkenes are hydrocarbon in which the carbon atoms are connected with double covalent bonds.

The general formula of alkenes is
`C_n H_(2n)` where n is the number of the carbon atoms present in a molecule of alkene.

• Alkynes are hydrocarbon in which the carbon atoms are connected with triple covalent bonds.

The general formula of alkynes is
`C_n H_(2n-2)` where n is the number of the carbon atoms present in a molecule of alkyne.

(a) An alkane with 22 carbon atoms

Putting n = 22 in the general formula of alkane, we get the formula of alkane as,
`C_(22)H_(2(22)+2)` or
`C_(22)H_(46)`

(b) An alkene with 17 carbon atoms

Putting n = 17 in the general formula of alkene, we get the formula of alkene as,
`C_(17)H_(2(17))` or
`C_(17)H_(34)`

(c) An alkyne with 13 carbon atoms

Putting n = 13 in the general formula of alkyne, we get the formula of alkyne as,
`C_(13)H_(2(13)-2)` or
`C_(13)H_(24)`