Question

How many grams of NaOH is needed to prepare 250 mL of 6.0 M solution?

a) 9 grams
b) 15 grams
c) 36 grams
d) 54 grams

Answer 1

To prepare a 6.0 M NaOH solution in 250 mL, you will need 60 grams of NaOH.

Step-by-step explanation:

To calculate the amount of NaOH needed to prepare a 6.0 M solution, we can use the formula:

Molarity (M) = moles of solute / liters of solution

First, let's calculate the moles of NaOH needed:

moles of NaOH = Molarity x liters of solution

Given: Molarity = 6.0 M, Volume of solution = 250 mL = 0.25 L

moles of NaOH = 6.0 M x 0.25 L = 1.5 moles

Next, let's calculate the grams of NaOH needed:

Grams of NaOH = moles of NaOH x molar mass of NaOH

The molar mass of NaOH is 40.00 g/mol.

Grams of NaOH = 1.5 moles x 40.00 g/mol = 60 grams

Therefore, option d) 54 grams is incorrect. The correct answer is option e) 60 grams.