Question

What is the mass of nickel(II) nitrate (182.71 g/mol) dissolved in 25.0 mL of 0.100 M Ni(NO3)2 solution? A) 157 g B) 0.250 g C) 4578 D) 0.4578 E) 4.00 g

Answer 1

Answer: 0.4578 g

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

$Molarity=\frac{n\times 1000}{V_s}$

where,

n= moles of solute

$Moles=\frac{\text{Given mass}}{\text{Molar mass}}=\frac{xg}{182.71g/mol}$  

$V_s$ = volume of solution  in ml = 25.0 ml

$0.100M=\frac{x\times 1000}{182.71\times 25}$

$x=0.4578g$

Thus 0.4578 g of nickel(II) nitrate is to be dissolved in 25.0 mL of 0.100 M $Ni(NO_3)_2$ solution.