Question

QUESTION 2How many grams of NaOH are present in 27.0 mL of a 2 M solution?

Answer 1

We want the mass of NaOH, Given:

V = 27.0 mL = 0.0270 L

C = 2 M

Given the concentration and volume we can find the number of moles of NaOH, and then convert it to mass.

C = n/V (or Molarity = moles of solute/litres of the solution) where C is the concentration or molarity, n is the number of moles of the solute and V is the volume of the solution

n = Cv

n = 2 x 0.0270 L

n = 0.054 mol

Now that we have the number of moles, we can get the mass of NaOH. Molar mass of NaOH = 39,997 g/mol

n = m/M where m is the mass and M is the molar mass

m = nM

m = 0.054 mol x 39,997 g/mol

m = 2.16 g