[mohd]

Asoulution of concentrated nitric acid has adensiyt of 1.51 g/m .

a) what is the molarity of this acid and what is th amolality of this solution?

[Borek]

Only with density tables.

Needles to say concentration calculator will do, but it just has density tables built in.

[mohd]

well , i don't have any idea about this problem ,, So if you don't mind to give me the solution details ,,

[Borek]

You have to find the concentration in the density tables. For that you have to find density tables. Density tables are in books. Books are in libraries. Sorry, but there is no more detailed help available. I can give you a ready answer, but you will not learn anything then.

You may have some luck googling for nitric acid density tables.

[Borek]

just density is not sufficient to calculate the molarity or molality. You have to mention the percentage of the solution.

Density is not enough to calculate concentration, but in most cases the relation between concentration and density is a bijection, so just knowing the density (and having density tables) is enough to find out concentration.

Sometimes it is not, for example for the acetic acid, but these are rare cases.

See example - that's for sulfuric acid. Only thing that I entered was density (1.2). Everything else was calculated automatically, with the use of built in density table.

[Borek]

What is the mathematical relation between density and concentration? Could you please explain in detail?

None. I mean - there are fitted curves that describe the relation, but as far as I know they don't have practical importance.

I think solutions with different concentrations have different density values. Now you can plot a relation and construct tables. But this is only usefull when your have the data with us. And each solution has its own table. Am I right?

Yes, that's why I was all the time referring to the density tables.

Note that measuring density of the solution is the easiest and fastest way of checking its concentration. Density measurement can be done fast with hydrometer. It is so often used some hydrometers are scaled not in g/mL (or Baume degrees or whatever) but in sulfuric acid mass % (or sucrose mass % in sugar and winemaking industries).

So, while you need tables, question that asks about molarity and molality of nitric acid of given density HAS unique and easy to find answer.