S K Malhotra Solutions for Chapter: Chemical Reactions and Equations, Exercise 1: Test Your Knowledge

In the chemical formula of rust ${\mathrm{Fe}}_2{\mathrm{O}}_3.\mathrm{Y}$

The value of Y in the formula can be-

A. Y = $5{\mathrm{H}}_2\mathrm{O}$

B. Y = ${\mathrm{xH}}_2\mathrm{O}$

C. Y = $10{\mathrm{H}}_2\mathrm{O}$

"Enter your correct answer as A, B or C."

Balance the following chemical equations and identify the type of reaction involved.

$\mathrm{F}{\mathrm{e}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+\mathrm{C}\mathrm{O}\left(\mathrm{g}\right)\to \mathrm{F}\mathrm{e}\left(\mathrm{s}\right)+\mathrm{C}{\mathrm{O}}_2\left(\mathrm{g}\right)$

Balance the following chemical equation and identify the type of reaction involved.

$\mathrm{F}\mathrm{e}\mathrm{S}{\mathrm{O}}_4\left(\mathrm{s}\right)\to \mathrm{F}{\mathrm{e}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+\mathrm{S}{\mathrm{O}}_2\left(\mathrm{g}\right)+\mathrm{S}{\mathrm{O}}_3\left(\mathrm{g}\right)\mathrm{}$

Explain why respiration is an exothermic reaction.

A colourless lead salt when heated produces a yellow residue and brown fumes.
(i) Name the lead salt (ii) Name the brown fumes (iii) Write the chemical equation for the reaction involved.

Name the term rancidity. Why is it caused? Suggest some measures to check rancidity.

Express the following facts in terms of a balanced chemical equation.
'When a strip of copper metal is placed in a solution of silver nitrate, metallic silver is precipitated and a solution containing copper nitrate is formed.

Why are decomposition reactions called the opposite of combination reactions? Explain with the help of equations.