Write the chemical equation of the reaction in which the following cha

1.	Write the chemical equation of the reaction in which the following changes have taken place with an example of each:(i) Change in colour (ii) Change in temperature (iii) Change in state
Answer» (i) Change in colour: Reaction between 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. (ii)Change in temperature: Action of dilute sulphuric acid on zinc. Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2 In this reaction, heat is EVOLVED (iii) Formation of precipitate: Action of barium chloride on SODIUM sulphate. BaCl2(aq) +Na2SO4(aq) → BaSO4(s) +2NaCl(aq)

Write the chemical equation of the reaction in which the following changes have taken place with an example of each:(i) Change in colour (ii) Change in temperature (iii) Change in state

Answer»

(i) Change in colour: Reaction between 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.

(ii)Change in temperature: Action of dilute sulphuric acid on zinc.

Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2

In this reaction, heat is EVOLVED

(iii) Formation of precipitate: Action of barium chloride on SODIUM sulphate.

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