Sourabh Monga Solutions for Chapter: Chemical Reactions and Equations, Exercise 2: PRACTICE QUESTIONS SET

Write the essential condition for the following reaction to take place

$2\mathrm{AgBr}\to 2\mathrm{Ag}+{\mathrm{Br}}_2$

Write one application of this reaction.

What is the colour of ferrous sulphate crystals? How does this colour change after heating?

Name the product formed on strongly heating ferrous sulphate crystals. What type of chemical reaction occurs in this change?

Write two examples from everyday life, where redox reactions are taking place.

Name the reducing agent in the following reaction:

$3{\mathrm{MnO}}_2+4\mathrm{Al}\to 3\mathrm{Mn}+2{\mathrm{Al}}_2{\mathrm{O}}_3$

State which is more reactive, Mn or Al and why?

When a metal X is treated with a dilute acid Y, then a gas Z is evolved which burns readily by making a little explosion.

(a) Name any two metals which can behave like metal X.

(b) Name any two acids which can behave like acid Y.

(c) Name gas Z.

(d) Is the reaction between metal X and dilute acid Y exothermic or endothermic.

In the following reaction between lead sulphide and hydrogen peroxide:

$\mathrm{PbS}\left(\mathrm{s}\right)+4{\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{aq}\right)\to {\mathrm{PbSO}}_4\left(\mathrm{s}\right)+4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$

Name the substance reduced and oxidised.

When water is added to a white solid X, a hissing sound is heard and a lot of heat is produced forming a product Y. A suspension of Y in water is applied to the walls of the house during whitewashing. A clear solution of Y is also used for testing ${\mathrm{CO}}_2$ gas in the laboratory. 
 (a) Identify the solid X and write its chemical formula. 
(b) Identify product Y and write its chemical formula. 
(c) What is the common name of the solution of Y which is used for testing carbon dioxide gas? 
(d) Write the chemical equation of the reaction which takes place on adding water to solid X.