Help!! Solubility/Acids and bases questions

May 2014
1
0
Hi, I am currently working on some chemistry homework and struggling hard. The questions deal with solubility and acids and bases. There are three questions in particular that I do not know how to do.

1. What would be the solubility of nickel (II) hydroxide in a 0.05M solution of strontium hydroxide? Determine the concentration of all ions in the solution.

2. What would be the pH, pOH, and ion concentrations in a solution prepared by mixing 0.04 moles of ammonia into 400mL of a 0.03M ammonium carbonate solution?

3. If 50mL of a 0.4M calcium chloride solution is mixed with 60mL of 0.5M sodium phosphate, determine the solubility, and the ion concentrations at equilibrium.

Any help is greatly appreciated because I am lost.
 
May 2010
491
8
Hi, I am currently working on some chemistry homework and struggling hard. The questions deal with solubility and acids and bases. There are three questions in particular that I do not know how to do.

1. What would be the solubility of nickel (II) hydroxide in a 0.05M solution of strontium hydroxide? Determine the concentration of all ions in the solution.

2. What would be the pH, pOH, and ion concentrations in a solution prepared by mixing 0.04 moles of ammonia into 400mL of a 0.03M ammonium carbonate solution?

3. If 50mL of a 0.4M calcium chloride solution is mixed with 60mL of 0.5M sodium phosphate, determine the solubility, and the ion concentrations at equilibrium.

Any help is greatly appreciated because I am lost.
In your High School Class are you shown Solubility Product
Equations? It would help you to Google this topic.Purdue U has excellent examples.
 
May 2014
2
0
The following may be the precise answers to your first question.

First step, find the molecular formula of Nickel(II) hydroxide and strontium hydroxide.
e.g. Nickelt(II) hydroxide : Ni(OH)2
You need it to be soluble in 0.05 M Strontium hydroxide.

In case of Ni(OH)2, it ionizes into one Ni2+ and 2OH-.
So the concentration of OH is twice as Ni.

You have 0.5 M x 2 OH = 1 M OH
0.5 M x 1 Ni2+ = 0.5 M Ni2+.
You can do the same calculation for Strontium hydroxide.

To answer to the solubility, Ni(OH)2 is quite soluble in water, acid and alkaline solutions. Strontium hydroxide is a caustic alkali. So Ni(OH)2 is quite soluble in 0.5 M of strontium hydroxide.

I hope that you got some answer from this.

Regards
Kesavan Devarayan
www.chesci.com
[email protected]
 
May 2010
491
8
Solubility

According to Langes Handbook of Chemistry
Sr(OH)2 has a solubility of 17.7 g per liter
Ni(OH)2 has a solubility of 13 mg per liter