Question

What would you need to do to calculate the molarity of 10g of NaCl in 2kg of water?

A. convert the 10 g of NaCl to Kg of NaCl
B. Convert the 10g of NaCl to moles of NaCl
C. Convert the 2kg of water to liters of water
D. Convert the 2kg of water to moles of water

Answer 1

B. Convert the 10g of NaCl to moles of NaCl

Answer 2

B) we will convert the 10 g of NaCl into moles.

Step-by-step explanation:

Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.

Formula:

Molarity = number of moles of solute / L of solution

we will convert the 10 g of NaCl into moles.

Number of moles of NaCl:

Number of moles = mass/molar mass

Number of moles = 10 g/ 58.44 gmol

Number of moles = 0.17 mol

1 Kg = 1 L

Molarity = 0.17 mol / 2 L

Molarity = 0.085 mol/L

Molarity = 0.085 M