The volumes of `4N HCI` and `10 N HCI` required to make 1 litre of `6N HCI` are

Options

A. `0.75` litre of `10 N HCI` and `0.25` litre of `4N HCI`
B. `0.25` litre of `4N HCI` and `0.75` litre of `10N HCI`
C. `0.67` litre of `4N HCI` and `0.33` litre of `10N HCI`
D. `0.80` litre of `4N HCI` and `0.20` litre of `10 N HCI`

Answer

B

Explanation

Let volume of 4 N HCl used = `upsilon mL`
therefore Volume of `10N HCl` used `= (1000 - upsilon) mL`
`NxxV = N_(1)V_(1)+N_(2)V_(2)`
`6xx1000=4xxupsilon+10(1000-upsilon)`
`6upsilon = 10000-6000`
`6 upsilon = 4000`
`upsilon = (4000)/(6) = 666.7 mL`
`=0.67 L`
Vol. of 4 NHCl used `= 0.67 L`
Vol. of 10 NHCl used `= 1-0.67 = 0.33 L`