Question

5. In the table given below, one of the changes has been listed under the wrong heading identify this change.

Physical Changes	Chemical Changes
freezing chocolate	the souring of food
whipping cream	making lemonade
squeezing oranges for juice	burning petrol in a motor car

Answer 1

Hint:

• No new substances are formed in a physical change, though the substance may change its shape and state.
• Chemical changes are those in which new substances are formed. The properties of the new substances formed are very different from the original substances.

Part 1: Physical change

• Freezing chocolate is a physical change because there is no formation of a new substance only the state of chocolate changes.
• Whipping cream is a physical change because there is no formation of a new substance. when the cream is whipped air puffs up the cream and the substances are still cream and air.
• Squeezing oranges for juice is a physical change because there is no formation of a new substance and no change in its properties.

Part 2: Chemical change

• The souring of food is a chemical change because the properties of food change. It becomes sour.
• Making lemonade is a physical change because there is no formation of a new substance. The powder and water do not combine chemically.
• Burning petrol in a motor car produces carbon dioxide and water which are new substances.

Conclusion: Hence, making lemonade is a physical change, which has been listed under the wrong heading.