Question

Chernisty Aegignment
Write two reactions for each
☆ the following characteristics
Change colour
Change state
evolution of gas
Evolution of heat
formation of precipitate please tell me


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Answer 1

change colous

Explanation:

evolution of the African state

Answer 2



Give one example each of a chemical reaction characterised by

1.Evolution of a gas. 

2.Change in colour. 

3.Formation of a precipitate. 

4.Change in temperature. 

ANSWER

1.Evolution of gas:

The chemical reaction between zinc and dilute sulphuric acid is characterized by the evolution of hydrogen gas.

Zn(s)+H2SO4(aq)→ZnSO4(aq)+H2(g)

2.Change in colour:

The reaction between the lead nitrate solution and potassium iodide solution.

Pb(NO3)2(aq)+2KI→PbI2(s)+2KNO3(aq)

In this reaction colour changes from colourless to yellow.

3.Formation of precipitate:

The action of Barium Chloride on sodium sulphate.

BaCl2(aq)+Na2SO4(aq)→BaSO4(s)+2KNaCl(aq)

4.Change in temperature change in temperature:

The action of dilute sulphuric acid on zinc:

Zn(s)+H2SO4(aq)→ZnSO4(s)+H2(g)

In this reaction, heat is evolved.

5.Change in the state:

When the wax is burnt in the form of the wax candle then Water and carbon dioxide are formed. Wax is solid water is a liquid whereas carbon dioxide gas.