How many grams of concentrated nitric acid solution should be used to prepare `250 mL` of `2.0 M HNO_(3)`? The concentrated acid is `70% HNO_(3)`:

Options

A. `"45.0 g conc HNO"_(3)`
B. `"90.0 g conc HNO"_(3)`
C. `"70.0 g conc HNO"_(3)`
D. `"54.0 g conc HNO"_(3)`

Answer

A

Explanation

250 mL of 2.0 M `HNO_(3)` will contain `HNO_(3)`
`=(2)/(1000)xx250=?0.5 mol "=0.5xx63 g = 31.5g`
As concentrated `HNO_(3)` is `70%` , therefore, concentrated `HNO_(3)` required `=(100)/(70)xx31.5g=45g`