How many moles of KBr are present in 200. mL of a 0.111 M solution?

Question

How many moles of KBr are present in 200. mL of a 0.111 M solution?
Express the amount in moles to three significant digits.

Answer 1

recall: volume * concentration = mass (moles in our case) 

 

First, let's simplify our units

 

200 mL = 0.2 L 

0.111 M = 0.111 moles/L

 

now use the above equation for mass:

 

0.2 L * (0.111 moles/L) = 0.0222 moles or 2.22 * 10^-2 moles