Questions: 0.871 M NaOH solution (density of solution = 1.04 g/mL ). Be sure your answer has the correct number of significant digits.

Solution Steps

The molar mass of NaOH is calculated by summing the atomic masses of its constituent elements:

• Na: 22.99 g/mol
• O: 16.00 g/mol
• H: 1.01 g/mol

\[ \text{Molar mass of NaOH} = 22.99 + 16.00 + 1.01 = 40.00 \, \text{g/mol} \]

Given the molarity (M) of the NaOH solution is 0.871 M, this means there are 0.871 moles of NaOH in 1 liter of solution.

\[ \text{Mass of NaOH} = \text{moles} \times \text{molar mass} = 0.871 \, \text{mol} \times 40.00 \, \text{g/mol} = 34.84 \, \text{g} \]

The density of the solution is given as \(1.04 \, \frac{\text{g}}{\text{mL}}\). Since 1 liter is 1000 mL, the mass of 1 liter of the solution is:

\[ \text{Mass of solution} = 1.04 \, \frac{\text{g}}{\text{mL}} \times 1000 \, \text{mL} = 1040 \, \text{g} \]

The mass of the solvent (water) can be found by subtracting the mass of NaOH from the total mass of the solution:

\[ \text{Mass of water} = \text{Mass of solution} - \text{Mass of NaOH} = 1040 \, \text{g} - 34.84 \, \text{g} = 1005.16 \, \text{g} \]

Final Answer