Answer:
Step-by-step explanation:
Hello,
In this case, considering the given specific gravity we are to compute the density of the 64% HNO3 solution:

In such a way, since the given solution of nitric acid is 64 % by mass, we've got:

Thus, by using the previously computed density and the molar mass of HA (90.2 g/mol) we can compute the required molar concentration as follows:

Regards.