Question

Find the molarity of water. Given: $\rho =1000kg/m^3$
[Report your answer after rounding off to the nearest integer].

Answer 1

Answer: 56

Density of water $=1000Kg/m^3=1g/mL$
Volume of water $=1L=1000mL$
Mass of $1.0L$ water $=1000g$
Molarity $=\frac{\text{ mass of water }}{\text{ molar mass of water }}\times \frac{1000}{v_{mL}}$
$\Rightarrow$ Molarity $=\frac{1000}{18}\times \frac{1000}{1000}=55.5mol{L}^{-1}$
Since before $5$ there is an odd digit so while rounding off we will add $1$ to the next digit.
So, final answer is $56.$