Question

A 1.5 M solution of NaOH was made in a laboratory. If the solution made had a volume of 4.5 L, how many grams of NaOH were added?

Answer 1

270g

Step-by-step explanation:

Given parameters:

Concentration of NaOH = 1.5M

Volume = 4.5L

Unknown

Mass of NaOH added = ?

Solution:

To solve the problem, we need to find the number of moles of the NaOH first;

Number of moles = concentration x volume

Number of moles = 1.5 x 4.5 = 6.75mol

Now;

Mass = Number of moles x molar mass

Molar mass of NaOH = 23 + 16 + 1 = 40g/mol

Mass = 6.75 x 40 = 270g