State whether the following are physical or chemical changes. 1. glowing of a bulb 2. burning of … 18. Boiling of an egg 19….
Answers:
- glowing of a bulb — physical change,
- burning of sugar — chemical change,
- heating of water — physical change,
- growing of a piglet into a pig — chemical change,
- burning of wood — chemical change,
- passing electric current through a heater rod — physical change.
- water cycle in nature — physical change,
- respiration in living beings — chemical change,
- shaping a piece of glass — physical change,
- lightning — chemical change,
- (energy produced) dissolving sugar in water — physical change,
- heating a mixture of iron filings and sulphur—chemical change.
- mixing oil with water — physical change.
- cutting wood into small pieces — physical change,
- photosynthesis — chemical change.
- Digestion of food — chemical change.
- Melting of wax — physical change.
- Boiling of an egg — chemical change.
- Slaking of lime — chemical change.