Two samples of `HCl` of `1.0 M` and `0.25 M` are mixed. Find volumes of these samples taken in order to prepare `0.75 M HCl` solution. Assume no water is added.
(I) `20 mL, 10 mL` (II) `100 mL, 50 mL`k
(III) `40 mL, 20 mL` (IV) `50 mL, 25 mL`

Options

A. I, II, III
B. I, II
C. II, III, IV
D. I, II, III, IV

Answer

D

Explanation

`((20 xx 1) +(10 xx 0.25))/(40 + 20) = 0.75 " " ((100 xx 1) + (50 xx 0.25))/(100 + 50) = 0.75`
`((40 xx 1) + (20 xx 0.25))/(40 + 20) = 0.75 " " ((50 xx 1) + (25 xx 0.25))/(50 + 25) = 0.75`