Question

100.0 mL of 3.8M NaCN, the minimum lethal concentration of sodium cyanide in blood serum

Answer 1

The given question is incomplete. The complete question is:

Calculate the number of moles and the mass of the solute in each of the following solution: 100.0 mL of 3.8 × 10−5 M NaCN, the minimum lethal concentration of sodium cyanide in blood serum

Answer: The number of moles and the mass of the solute are $0.38\times 10^{-5}$ and $18.62\times 10^{-5}g$ respectively

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

$V_s$ = volume of solution in ml

$3.8\times 10^{-5}M=\frac{n\times 1000}{100.0}$

$n=0.38\times 10^{-5}$

n = moles of $NaCN$ = $\frac{\text {given mass}}{\text {Molar mass}}$

$0.38\times 10^{-5}=\frac{x}{49g/mol}$

$x=18.62\times 10^{-5}g$

Thus the number of moles and the mass of the solute are $0.38\times 10^{-5}$ and $18.62\times 10^{-5}g$ respectively