Strontium Nitrate and Ammonium Hydroxide Reaction: Formation of Precipitate

[Sace Ver]

Homework Statement

Strontium Nitrate + Ammonium Hydroxide =

Homework Equations

Finding net ionic equation

The Attempt at a Solution

Balanced Equation:
Sr(NO₃)₂(aq) + NH₄OH (aq) = Sr(OH)₂(aq) + NH₄NO₃ there is no precipitate correct? I will not need to find the net-ionic equation.

 

[SteamKing]

Homework Statement

Strontium Nitrate + Ammonium Hydroxide =

Homework Equations

Finding net ionic equation

The Attempt at a Solution

Balanced Equation:
Sr(NO₃)₂(aq) + NH₄OH (aq) = Sr(OH)₂(aq) + NH₄NO₃ there is no precipitate correct? I will not need to find the net-ionic equation.

Not all hydroxides are water-soluble:

https://en.wikipedia.org/wiki/Strontium_hydroxide

 

[Sace Ver]

Not all hydroxides are water-soluble:

https://en.wikipedia.org/wiki/Strontium_hydroxide

I was doing a lab today and no precipitate formed.

 

[SteamKing]

I was doing a lab today and no precipitate formed.

Well, it all depends on how much Sr hydroxide you made and how much water there is.

The solubility figures for Sr hydroxide are given in the Wiki article.

You can contrast those solubility figures with comparable ones for ammonium nitrate:

https://en.wikipedia.org/wiki/Ammonium_nitrate

 

[Borek]

It is rather easy to estimate.

pH of a 1 M ammonia solution is around 11.2, so [OH^-] = 4.2×10^-3

Different sources list different values for solubility product of Sr(OH)₂, but apparently it is around 10^-4.

That means using 1 M ammonia you should not expect precipitate unless concentration of the Sr²⁺ is around 6 M.

Using more concentrated ammonia (3 M) will shift the required Sr²⁺ concentration down to 1.9 M, still quite high.

No wonder you couldn't see any precipitate. For that you would need a strong base like NaOH or KOH.