Q3 An unknown green solution is heated with a piece of aluminum foil and sodium hydroxide solution.

(i) The gas produced turns damp red litmus paper blue.  Name the gas evolved


Its ammonia gas


(ii) This is a confirmatory test for an anion.  Name this anion.


The anion is nitrate ion (NO3 -)


(iii) Give a possible cation which gives the green solution.

Q2 Ammonium sulfate is heated with sodium hydroxide.

(ii)  Describe a test for the gas

Hold a piece of damp red litmus paper over the mouth of the test tube. When the damp red litmus paper turns blue, it mean that ammonia gas is produce.

Q2 Ammonium sulfate is heated with sodium hydroxide

(i) Write a chemical equation (include state symbols) for the reaction.
 

•(NH4)2 SO4 (aq) + 2NaOH (aq) --> Na2 SO4 (aq) + 2H2O (l) + 2NH3 (g)

1. Zinc nitrate reacts with aqueous ammonia (NH4OH) to form a salt and a base.

(iv) Write an ionic equation for the reaction.  

 Zn 2+ (aq) + 2OH - (aq) -> Zn(OH)2 (s)

Q1 Zinc nitrate reacts with aqueous ammonia (NH4OH) to form a salt and a base.

(iii) Write a chemical equation for the reaction (include state symbols).

 Zn(NO3)2 (aq) + 2NH4OH (aq) --> 2NH4NO3 (aq) + Zn(OH)2 (s)

Q1 Zinc nitrate reacts with aqueous ammonia (NH4OH) to form a salt and a base.

(ii) Describe the observations for the reaction

When zinc nitrate solution reacts with ammonium hydroxide (both colourless), a white precipitate of zinc hydroxide is will be produced .

Q1 Zinc nitrate reacts with aqueous ammonia (NH4OH) to form a salt and a base

(i) Name the salt and the base.

Salt is ammonium nitrate. Base is zinc hydroxide.