Find the ratio of volumes of `2M HNO_(3)` and `5M HNO_3 ` required to mix in order to prepare one litre of `3M HNO_3` solution.

Explanation

Resultant concentration of the mixture , `N = (V_1N_1 + V_2N_2)/(V_1 + V_2)`
`3 = (x xx 2 + (1000 - x)5)/(x + 1000 - x) = (2x + 5000 - 5x)/(1000)`
`3000 = 5000 - 3x , 3x = 2000, x = 667 ml , 1000 - x = 333 ml`
The ratio of the volumes of `2N HNO_3` and `5N HNO_3 = 667.333 = 2 : 1`.