Question

Sample A: 300 mL of 1M sodium chloride

Sample B: 145 mL of 1.5 M sodium chloride

Which sample contains the larger concentration of sodium chloride?

Answer 1

Sample A

Step-by-step explanation:

Molarity of a solution can be calculated using the formula:

Molarity = number of moles (mol) ÷ volume (vol)

For Sample A:

V = 300ml = 300/1000 = 0.3 L

Molarity = 1M

n = number of moles (mol)

1 = n/0.3

n = 0.3moles

For Sample B:

V = 145 mL = 145/1000 = 0.145L

Molarity = 1.5 M

n = number of moles

1.5 = n/0.145

n = 1.5 × 0.145

n = 0.22 moles

Based on the above results (moles), sample A with 0.3 moles contains the larger concentration of sodium chloride.