Question

Why nitric acid cannot be concentrated beyond 68% by boiling?

Answer 1

It is because at 68% concentration it forms a constant boiling mixture, i.e., if heated beyond this concentration then proportion of water vapour and nitric acid vapour, leaving the dilute acid does not change. Thus, it cannot be concentrated by boiling. nitric acid.

Answer 2

It is because at 68% concentration it forms a constant boiling mixture, i.e., if heated beyond this concentration then proportion of water vapour and nitric acid vapour, leaving the dilute acid does not change. Thus, it cannot be concentrated by boiling. nitric acid.