The decreasing order of acidic character among ethane(),ethene(II). Ethyne(III) and propyne (IV) is

Options

A. `I gt II gt III gt IV`
B. `II gt III gt I gt IV`
C. `III gt IV gt II gt II`
D. `IV gt III gt II gt I`

Answer

C

Explanation

The correct order of decreasing acidity is
`HC=CH lt HC= C-CH_(3) lt H_(2)C=CH_(2) gt H_(3)C-CH_(3)`
Hydrogen atoms attached to sp-hybridized carbon atom are most acidic, followed by those attached to `sp^(2)` hybridized carbon atom, and those attached to `sp^(3)` hybridized are least acidic.