Question

What is the molarity of a solution that has 5.000 grams of NaOH dissolved to make 700.0 mL of solution?

Na= 22.99 g/mol
O= 16.00 g/mol
H= 1.01 g/mol

Answer 1

0.178 M

Step-by-step explanation:

First we determine the molar mass of NaOH, using the given molar masses of the elements:

• Molar Mass of NaOH = Molar Mass of Na + Molar Mass of O + Molar Mass of H

• Molar Mass of NaOH = 40 g/mol

Then we convert 5.000 grams of NaOH into moles, using its molar mass:

• 5.000 g ÷ 40 g/mol = 0.125 mol

Now we convert 700.0 mL into L:

• 700.0 mL / 1000 = 0.700 L

Finally we calculate the molarity of the solution:

• Molarity = moles / liters

• 0.125 mol / 0.700 L = 0.178 M