Question

Question 2 (Mandatory) (1 point)The concentration of a 0.50 L solution containing 9.0 g of sodium chloride isa) 18 mol/Lb) 0.31 mol/Lc) 0.055 mol/Ld) 114 mol/L

Answer 1

Answer

b) 0.31 mol/L

Explanation

Given that:

Volume of solution = 0.50 L

Mass of sodium chloride = 9.0 g

What to find:

The concentration of the sodium chloride solution.

Step-by-step solution:

The first step is to convert 9.0 g NaCl to moles using the mole formula.

$\begin{gathered} Moles=\frac{Mass}{Molar\text{ }mass} \\ \\ The\text{ }molar\text{ }mass\text{ }of\text{ }NaCl=58.44g\text{/}mol \\ \\ Moles\text{ }of\text{ }NaCl=\frac{9.0g}{58.44g\text{/}mol}=0.154004106\text{ }mol \end{gathered}$

Hence, the concentration of the NaCl solution can be calculated using the molarity formula.

$\begin{gathered} Concentration\text{ }of\text{ }NaCl\text{ }solution=\frac{Moles\text{ }of\text{ }NaCl}{Volume\text{ }of\text{ }solution} \\ \\ Concentration\text{ }of\text{ }NaCl\text{ }solution=\frac{0.154004106\text{ }mol}{0.50\text{ }L}=0.31\text{ }mol\text{/}L \end{gathered}$

The concentration of a 0.50 L solution containing 9.0 g of sodium chloride is thus b) 0.31 mol/L