Question

Performing and obseving the following reactions and classifying them into :
a) combination reaction
b) Decomposition reaction
c) Displacement reaction
d) Double displacement reaction
I) Action of water on quicklime
ii) Action of heat on ferrous sulphate crystals
III) Iron nailks kept in copper sulphate solution
iv) Reaction between sodium sulphate and barium choride solution​

Answer 1

${\underline{\underline{\huge{\mathscr{\orange{Answer:-}}}}}}$

Ferrous sulphate crystals are ferrous sulphate heptahydrate with a chemical formula FeSO4.7H2O and are green in colour.

On eating the ferrous sulphate heptahydrate it loses seven water molecules to form anhydrous ferrous sulphate (FeSO4) and is white in colour. The reaction is as follows:

Heat

FeSO4.7H2O → FeSO4(s) + 7H2O ………….(1)

(Green colour) (white colour)

Ferrous sulphate when heated is decomposed to ferric oxide, sulphur trioxide, and sulphur dioxide. The reaction is as follows:

Heat

FeSO4(s) → Fe2O3(s) + SO2(g) + SO3(g) ………….(2)

(White colour) (brown colour) (colourless) (colourless)

In the reaction (2) one substance FeSO4 (Ferrous sulphate) splits into three substances ferric oxide (Fe2O3), sulphur dioxide (SO2), and sulphur trioxide (SO3) due to heat. Therefore this reaction is called decomposition reaction or also known as a thermal decomposition reaction.

We can combine reaction (1) and (2) and write it as follows:

2FeSO4.7H2O(s) → Fe2O3(s) + SO2(g) + SO3(g) + 14H2O(g)

Procedure

Wash a boiling tube with distilled water and dry it.

Take 2 grams of ferrous sulphate crystals in the tube.

Make a note of the colour of the crystals.

Use a test tube holder to hold the boiling tube.

Heat the boiling tube on the bunsen burner as shown in the figure.

Observe the colour of the residue got and smell the odour of the gases evolved.

Tiny colourless water droplets are seen near the neck of the tube.

Gently turn it towards your nose and smell for any gas evolved.

Wet blue and red litmus paper strips.

Hold the litmus paper strips near the mouth of the boiling tube.

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀

$\sf\pink{❥CharmingBeauty}$