Question

A chemist prepares a solution of aluminum chloride by measuring out of aluminum chloride into a volumetric flask and filling the flask to the mark with water. Calculate the concentration in of the chemist's aluminum chloride solution. Be sure your answer has the correct number of significant digits.

Answer 1

0.15M

Step-by-step explanation:

Molar Concentration =
`(mass)/(molar mass)`

Assuming 20g of the unadulterated aluminium chloride was weighed into the volumetric flask, and given molar mass of AlCl3 = 133.34g/mol

∴ Molarity =
`(20)/(133.34)`

= 0.14999 ≈ 0.15M (to 2 significant figures)

I hope this solution is clear. The same can be calculated from concentration by volume.