Question

What’s the mass of NaCL is in 0.625L of 0.207M solution

Answer 1

The mass of NaCl is 7.5 grams

Step-by-step explanation

Given that;

The volume of the solution is 0.625L

The molarity of the solution is 0.207 M

Follow the steps below to find the mass of NaCl

Step 1; Find the number of moles using the below formula

`\begin{gathered} \text{ Molarity =}\frac{moles\text{ of solute}}{\text{ volume of solution}} \\ \end{gathered}`
`\begin{gathered} \text{ 0.207 = }\frac{\text{ moles of solute}}{\text{ 0.625}} \\ \text{ cross multiply} \\ \text{ moles of solute = 0.207 }*\text{ 0.625} \\ \text{ moles of solute = 0.1294 mole} \end{gathered}`

Step 2; Find the mass of NaCl using the below formula

`\begin{gathered} \text{ mole = }\frac{\text{ mass}}{\text{ molar mass}} \\ \text{ cross multiply} \\ \text{ mass = mole }*\text{ molar mass} \end{gathered}`

Recall, that the molar mass of NaCl is 58.44g/mol

`\begin{gathered} \text{ mass = 0.1294 }*\text{ 58.44} \\ \text{ mass = 7.5 grams} \end{gathered}`

Therefore, the mass of NaCl is 7.5 grams