Question

It takes 83mL of a 0.45M NaOH solution to neutralize 235mL of an HCl solution.

What is the concentration of HCl solution?

Answer 1

`M_(acid)=0.16M`

Step-by-step explanation:

Hello there!

In this case, according to the reaction between hydrochloric acid and sodium hydroxide:

`HCl+NaOH\rightarrow NaCl+H_2O`

Whereas the 1:1 mole ratio of the acid to base allows us to write:

`n_(acid)=n_(base)`

At the equivalence point (complete neutralization); it is possible for us to write it in terms of molarities and volumes as follows:

`M_(acid)V_(acid)=M_(base)V_(base)`

In such a way, we solve for the molarity of the HCl to obtain:

`M_(acid)=(M_(base)V_(base))/(V_(acid)) \\\\M_(acid)=(83mL*0.45M)/(235mL)\\\\M_(acid)=0.16M`

Best regards!