Question

Volume-Volume percent:

10 mL ice cold 4 % acetic acid in 95 % ethanol (v/v)

1. how many mL of acetic acid and how many mL of ethanol is needed to make 10 mL mixture of the two

Answer 1

Ans. Given,     10.0 mL ice cold 4% acetic acid in 95% ethanol (v/v)

It’s assumed that all concentrations are in terms of % (v/v).

# In above solution-

            Final volume of solution = 10.0 mL

            Volume of ethanol = 95%

            Volume of acetic acid = 4%

# A 95% (v/v) means than there is 95% of absolute ethanol per 100 mL solution.

So,

            Required volume of ethanol = 95% of Final volume of solution

                                                            = 95% x 10.0 mL

                                                            = 9.5 mL

Required volume of acetic acid = 4% of Final volume of solution

                                                            = 4% x 10.0 mL

                                                            = 0.4 mL