Problem: A 100.0-mL aliquot of 0.200 M aqueous potassium hydroxide is mixed with 100.0 mL of 0.200 M aqueous magnesium nitrate. What mass of precipitate is produced?

FREE Expert Solution
84% (293 ratings)
FREE Expert Solution

We first need to determine the products that will form when potassium hydroxide, KOH, and magnesium nitrate, Mg(NO3)2, are mixed. There will be a double displacement reaction, where KOH and Mg(NO3)2 will switch ions. This means KNO3 and Mg(OH)2 will form.

According to solubility rules, nitrates are soluble while hydroxides are insoluble, except when paired with Group 1A ions and NH4+. This means KNO3 is soluble and will dissolve in solution while Mg(OH)2 is insoluble and will precipitate out. The chemical reaction is:

2 KOH(aq) + Mg(NO3)2(aq) → 2 KNO3(aq) + Mg(OH)2(s)

We then need to determine which between KOH and Mg(NO3)2 is the limiting reactant. The limiting reactant will form the less amount of Mg(OH)2.

84% (293 ratings)
Problem Details

A 100.0-mL aliquot of 0.200 M aqueous potassium hydroxide is mixed with 100.0 mL of 0.200 M aqueous magnesium nitrate. What mass of precipitate is produced?

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Solution Stoichiometry concept. You can view video lessons to learn Solution Stoichiometry Or if you need more Solution Stoichiometry practice, you can also practice Solution Stoichiometry practice problems .

How long does this problem take to solve?

Our expert Chemistry tutor, Bethany took 7 minutes to solve this problem. You can follow their steps in the video explanation above.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Fatima's class at UWATERLOO.

What textbook is this problem found in?

Our data indicates that this problem or a close variation was asked in . You can also practice practice problems .