Questions & Answers

Question

Answers

Calculate the value of 100x if x mL is the volume of acid that contains 63 g pure acid:

A. 63.38

B. 63.00

C. 63.20

D. None of these

Answer
Verified

Let us start solving this question step by step:

Step (1) The density of $\text{HN}{{\text{O}}_{3}}$ solution is 1.42 g/mL means that 1 mL of volume has 1.42 grams of $\text{HN}{{\text{O}}_{3}}$ and 100 mL of volume has 70 grams of $\text{HN}{{\text{O}}_{3}}$.

So, the mass of pure $\text{HN}{{\text{O}}_{3}}$ in 100 mL of volume is $70\times 1.42$ grams or 99.4 grams.

Step (2) The volume of acid will be found by unitary method as

99.4 grams of pure acid is present in 100 mL of volume,

Then, 63 grams of pure acid will be present in $\dfrac{100\times 63}{99.4}$ mL of volume which is equal to 63.38 ml.

The volume of acid will be 63.38 mL of acid.

The value of 100x is 63.38 mL. As, we were already dealing with 100 mL of volume.