Subject Experts Solutions for Chapter: Physical and Chemical Changes, Exercise 1: Practice Exercise

Which of the following represent a chemical change?

$\mathrm{I}$. Magnetisation of iron.
$\mathrm{II}$. Condensation to liquid.
$\mathrm{III}$. Burning of fuel.
$\mathrm{IV}$. Rusting of iron.

Which of the following processes is related to chemical change?

$\mathrm{I}$. Movement of free electrons in copper wire.
$\mathrm{II}$. Electric current passes through copper wire.
$\mathrm{III}$. Electric current passes through $\mathrm{NaCl}$ aqueous solution.

Which of the following processes responsible for chemical change?

$\mathrm{I}$. Electrolysis
$\mathrm{II}$. Sublimation
$\mathrm{III}$. Corrosion
$\mathrm{IV}$. Decomposition

Code

Statement$-\mathrm{I}:$Conversion of blue copper sulphate to black cupric oxide on heating is a physical change.

Statement$-\mathrm{II}:$ A change in which, chemical composition does not change is called physical change.

Statement $\mathrm{I}-$ The blue colour of copper sulphate crystal disappears when it is heated strongly.

Statement $\mathrm{II}-$Due to heating water of crystallisation of crystal is lost.

Which one among the following is not a chemical change? 

A sample of carbon dioxide that undergoes a transformation from solid to liquid and then to gas would undergo

Which one of the following is not a chemical change?