[Chemistry] How do you find the new concentration?

[jkh4]

Homework Statement

For solution A the concentration is 7.00x10^-4 mol/L. You transfer 10ml of the solution A out into a 10 dram vial and add 10mL of 0.1M HCL acid solution, and the new mixture is called solution B. What is the concentration of solution B?

Homework Equations

The Attempt at a Solution

is this right approach? first find the mol of solution A, and then find the mol of HCl. Add them together and divided by the total volume.

Thanks.

 

[chemisttree]

I guess it would depend on if the HCl would react with the material in the stock solution.