Question:
4.5 g of compound A (MW = 90) was used to make 250 mL of its aqueous solution. The molarity of the solution in M is x × 10–1. The value of x is ________. (Rounded off to the nearest integer)
Solution:
$\mathrm{M}=\frac{4.5 / 90}{250 / 1000}=0.2$
$=2 \times 10^{-1}$