Question #3d2dd

1 Answer

Answer:

You get a precipitate of iron(III) hydroxide, #Fe(OH)_3(s)#.

Explanation:

The net equation is:

#OH^"-"(aq) + Fe^"3+"(aq) -> Fe(OH)_3(s)#

This double displacement reaction is driven by the very low solubility of iron(III) hydroxide (#5.3*10^"-5" "g"//"100 g of water"#) at 20 °C).

#3KOH(aq) + Fe(NO_3)_3(aq) -> Fe(OH)_3(s) + 3KNO_3(aq)#

Potassium (#K^"+"(aq)#) and nitrate (#NO_3^"-"(aq)#) are spectator (unchanged) ions.

Filter out the iron(III) hydroxide precipitate and you'll have a solution of pure potassium nitrate, #KNO_3(aq)#.

After evaporation of water, if there isn't any excess of iron(III) or hydroxide, we can eventually crystallise a solid sample of the second product: #KNO_3#.