Question #d755f

1 Answer
Feb 17, 2016

Answer:

375 mL of water is needed.

Explanation:

Using the dilution formula, calculate first for the amount of 2.0 M NaOH needed to prepare 500 mL of 0.5M NaOH solution:

let:
#C_1#= initial concentration of NaOH solution
#C_2#= final concentration of NaOH solution
#V_1# = volume needed
#V_2# = total volume of resulting solution

So then:

#C_1V_1=C_2V_2#
#V_1=(C_2V_2)/(C_1)#

#V_1=(color(blue)cancel(0.5 M)(500 mL))/color(blue)cancel(2.0 M)#

#V_1= 125# #mL#

Then to calculate for the volume of water needed, subtract the volume of the final solution with the computed volume of 2.0 M NaOH needed:

#V_(water)= 500 mL - 125 mL#
#V_(water)= 375 mL#