Which of the following solutions have the same molar concentration ?

Options

A. 20 g of NaOH in 200 mL of solution
B. 0.5 mole of KCl in 200 mL of solution
C. 40 g of NaOH in 100 mL of solution
D. 20 g of KOH in 200 mL of solution

Answer

A, B

Explanation

(a) `M=((20g)//(40"g mol"^(-1)))/(200//1000L)`
`=2.0 mL^(-1)`
(b) `M=((0.5 mol))/(200//1000L)`
`=2.5 "mol L"^(-1)`
(c) `M=((40g)//("40 g mol"^(-1)))/(100//1000mL)`
`=10.0 "mol L"^(-1)`
(d) `M=((20g)//("56 g mol"^(-1)))/(200//1000L)`
`=1.79"mol L"^(-1)`
`:.` (a) and (b) are both correct.