Question

if 120g of urea is dissolved in 1000g of water find molarity of solution, density of solution is 1.12g/ml​

Answer 1

Answer:

Molarity of solutions is 2.24 .

Explanation:

molarity = no. of moles / volumes of solutions

Molarity = 2 / 0.89285

molarity = 2.24

Answer 2

Answer:

The molarity of the solution ( urea + water ) calculated is $2M$.

Explanation:

Data given,

The given mass of urea, $m_{urea}$ = $120g$

The given mass of water, $m_{water}$ = $1000g$

The solution's given density, ρ = $1.12g/ml$ = $1120g/L$

The molarity of solution ( urea + water ) =?

As we know,

• Molarity = $\frac{Number of moles (solute)}{Volume ( solution )}$   -------equation (1)

Now,

• The solution's total mass = $m_{urea} + m_{water}$ = $120 + 1000$ = $1120g$.

As we know,

• Density = $\frac{Mass}{Volume}$
• The solution's volume = $\frac{Mass}{Density}$ = $\frac{1120}{1120}$ = $1L$

Now, we have to calculate the number of moles of solute.

• Number of moles = $\frac{m_{urea}}{M_{urea}}$

Here, $M_{urea}$ is the molar mass of urea = $60g/mol$

Therefore,

• Number of moles = $\frac{120}{60}$ = $2mol$

After putting the calculated values of the number of moles and the volume of the solution in equation (1), we get:

• Molarity = $\frac{2}{1}$ = $2M$

Hence, the molarity of the solution ( urea + water ) calculated is $2M$.