Given :
Initial concentration of nitric acid, [tex]C_1 = 16\ M[/tex].
Final concentration of nitric acid, [tex]C_2 = 0.250 \ M[/tex].
Volume of [tex]HNO_3[/tex], [tex]V _2= 500\ mL = 0.5\ L .[/tex]
To Find :
Volume needed( [tex]V_1[/tex] ).
Solution :
We know,
[tex]C_1V_1 =C_2V_2\\\\16 \times V_1 = 0.250 \times 0.5 \\\\V_1 = \dfrac{0.250 \times 0.5}{16}\\\\V_1 = 0.0078125\ L = 7.8125 \ mL[/tex]
Hence, this is the required solution.
