Question

Which of the following is/are chemical change(s)?

• A. Dissolving of an iron nail in acid
• B. Breaking of ice
• C. Charring of sugar
• D. Dissolving alcohol in water

Answer 1

Answer: (A), (C)

The correct options are
A Dissolving of an iron nail in acid
C Charring of sugar

$\bullet$ When iron nails get dissolved in water, iron actually reacts to form salt and hydrogen gas. Hence, this is a chemical change.
$\bullet$ Breaking of ice doesn't change the chemical composition of ice and hence, it is a physical change.
$\bullet$ Charring is a chemical process of incomplete combustion of certain solids when subjected to high heat. Hence, charring of sugar is a chemical change as the composition of sugar gets changed.
$\bullet$ When alcohol is dissolved in water, both the components just get mixed but their compositions are not changed. Hence, it is a physical change.