Question

If it took 30.0 mL of 0.50 M NaOH to neutralize 15.0 mL of HNO3, what is the concentration of the HNO3? Explain and show on the white board how titration is used to find the amount of NaOH it took to neutralize the HNO3.

Answer 1

The equation for this is NaOH + HNO3 --> H2O + NaNO3, a double displacement (titration) reaction. This is already a balanced reaction, so we can solve for the concentration of HNO3 using:
(30.0 mL)(0.50 M NaOH) = (15.0 mL)x
x = 1.00 M HNO3

If we have the HNO3 solution (of unknown concentration), titration is the process of slowly dropping the NaOH (of known concentration) into the solution. With an appropriate indicator, a visible color change will be seen, signifying the end point. This allows us to estimate the concentration of the HNO3 solution.