Q10 of 39 Page 1

What is observed when a solution of potassium iodide solution is added to a solution of lead nitrate? (CBSE 2014, 2013)

i. When lead nitrate reacts with potassium iodide, it forms a yellow coloured precipitate of lead iodide along with potassium nitrate.


ii. This type of reaction is a double displacement reaction.


iii. [PbNO3]2 + 2KI → 2KNO3 + PbI2


Here,


PbNO3 is lead nitrate.


KI is potassium iodide.


KNO3 is potassium nitrate.


PbI2 is lead iodide.


OR


i. X is Cu.


Y is CuO.


ii. This a redox chemical reaction. Here, copper gets oxidised by heating to copper oxide, and hydrogen reduces copper oxide back to copper.


iii. Cu + O2 → 2CuO


CuO + H2 → Cu + H2O

More from this chapter

All 39 →
8

Giving an example list two information which make a chemical equation more useful (informative). (CBSE 2015)

 9

Why are decomposition reaction called the opposite of combination reaction. 
(CBSE 2010)

 11

Identify the type of chemical reaction taking place

i. on making a solution of potassium chloride with silver nitrate, an insoluble white substance is formed.

ii. on heating green coloured ferrous sulphate crystals, reddish-brown solid is left and the smell of a gas having the odour of burning Sulphur is observed. (CBSE 2007)
 

 7

Write the balanced chemical equation for the following reaction and identify the type of reaction and define it.

Iron III oxide reacts with Aluminium and gives molten iron and aluminium oxide. (2012)