When 10mL of ethyl alcohol (density `=0.7893gmL^(-1)`) is mixed with 20mL of water (density `0.9971 gmL^(-1)`) at `25^(@)C`, the final solution has a density of `0.9571 gmL^(-1)`. The percentage change in total volume on mixing is

Options

A. `3.1%`
B. `2.4%`
C. ` 1%`
D. `5%`

Answer

A

Explanation

Total weight of alcohol and water `= 10 xx 0. 7893 + 20 xx 0.9971`
Volume of mixture `= (10 xx 0. 7893 + 20 xx 0. 9971)/( 0. 95. 71) = 29 . 08 mL`
Change in Volume `= (20 + 10) - 29. 08 = 0. 92 mL`
`%` change in volume `= (0. 92 xx 100)/( 30) = 3. 06 % ~~ 3. 1 %`