A student was asked to perform two experiments in the laboratory based on the instructions given:
Observe the picture given below and state one observation for each of the Experiments 1 and 2 that you would notice on mixing the given solutions.

(a) Experiment 1

(b) Experiment 2

Experiment 1:

Mixing Zinc Sulphate and Barium Chloride
Observation: A white precipitate is formed immediately upon mixing the two colourless solutions.
Explanation: This is a double displacement reaction. The Barium ions Ba²⁺ react with the Sulphate ions SO₄^2- to form Barium Sulphate BaSO₄, which is an insoluble white solid.

$\underset{\text{colourless solution}}{\text{ZnSO}$4{(aq)}} + \underset{\text{colourless solution}}{\text{BaCl}2{(aq)}} \longrightarrow \underset{\text{white precipitate}}{\text{BaSO}4{(s)}\downarrow} + \underset{\text{colourless in solution}}{\text{ZnCl}2{(aq)}}

Experiment 2:

Adding Ammonium Hydroxide to Copper Hydroxide
Observation: The pale blue precipitate of copper hydroxide dissolves to form a deep blue (inky blue) solution.
Explanation: Copper(II) hydroxide reacts with excess ammonium hydroxide to form a soluble complex called Tetraammine copper(II) hydroxide. This complex is responsible for the characteristic deep blue color.

\underset{\text{pale blue precipitate}}{\text{Cu(OH)}2{(aq)}} + \underset{\text{colourless solution}}{4\text{NH}4\text{OH{(aq)} (excess)}} \longrightarrow \underset{\text{deep blue solution}}{[\text{Cu(NH}3)4](\text{OH})2{(aq)}} + \underset{\text{water}}{4\text{H}2\text{O}}