What mass of NaCl (in grams) is present in 0.75 L of a 0.115 M NaCl solution?

• A. 3.22 g
• B. 5.04 g
• C. 1.29 g
• D. 6.44 g

Answer: (B)

Verified step by step guidance

1. Identify the given information: volume of solution (V) = 0.75 L, molarity (M) = 0.115 mol/L, and the solute is NaCl.
2. Recall the definition of molarity: \(M = \frac{\text{moles of solute}}{\text{liters of solution}}\). Use this to find the moles of NaCl by rearranging the formula: \(\text{moles of NaCl} = M \times V\).
3. Calculate the moles of NaCl by multiplying the molarity by the volume: \(\text{moles of NaCl} = 0.115 \times 0.75\).
4. Find the molar mass of NaCl by adding the atomic masses of sodium (Na) and chlorine (Cl): \(\text{molar mass of NaCl} = 22.99 + 35.45\) g/mol.
5. Convert moles of NaCl to grams using the molar mass: \(\text{mass of NaCl} = \text{moles of NaCl} \times \text{molar mass of NaCl}\).