Physical and Chemical Changes
Trending Questions
Why is the ripening of fruits considered a chemical change?
Change A: LPG exists as a liquid inside the cylinder and it get converted to gas on coming out.
Change B: LPG burns to produce heat.
Which of the following are correct?
- Change A- Physical
- Change B- Physical
- Change A- Chemical
- Change B- Chemical
Which of the following is not an example of a physical change?
Cutting of wood
Burning of wood
Breaking of glass
Melting of gold
- Chemical change
- Reversible change
- Physical change
- Irreversible change
- True
- False
5 (a).Classify the following changes as physical and chemical change
Fermentation of sugar solution to alcohol
Which of the following changes can be reversed?
Raw Egg to Boiled Egg
Wet Clothes To Dry Clothes
Bud to Flower
Cow Dung to Biogas
Boiling of milk in a pan is a physical change.
- True
- False
In winter we sometimes end up in fogging a mirror with our breath. Have you ever wandered what kind of change is that? After all the fog disappears after some time.
Chemical change
Physical change
Cannot be ascertained as the combination of air was not given
None of these
Is clotting of blood physical or chemical change? (with reason)
- Reversible
- Irreversible
- Physical
- Chemical
1. Souring of milk is a __________ change.
If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.
(a) Do you think rust is different from iron?
(b) Can you change rust back into iron by some simple method?
(c) Do you think the formation of rust on iron is a chemical change?
(d) Give two other examples of a similar type of change.
Fill in the blank :
Chemical changes are :
(a) always reversible. (d) mostly reversible
(b) always irreversible
(c) mostly irreversible
When water is absorbed by paper towel, what kind of change are we observing?
None of these
Physical change
Chemical change
Cannot be ascertained
Changing state of water is a chemical or physical change
State why addition of sodium chloride to water is considered a physical change, while addition of dilute sulphuric acid to zinc is considered as chemical change.
Four students have their own opinion about reversible and irreversible changes. Who among the following is correct?
Rohan: Both physical and chemical changes are reversible.
Sam: Both physical and chemical changes are irreversible.
Tom: Physical changes are irreversible and chemical changes are reversible.
Riah: Chemical changes are irreversible and physical changes are reversible
Rohan
Sam
Tom
Riah
- No new substance is formed.
- We cannot reverse this change.
- A change in chemical composition occurs.
- A change in size or shape occurs.
Difference between physical change and chemical change with example
Statement II: The burning of wick for the production of heat and light is a chemical change.
- Both statements are true
- Both statements are false
- Only statement I is true
- Only statement II is true
During a chemical reaction, if the products have more chemical energy than the reactants,
energy is released
no changes in energy
energy is absorbed
depends
Classify the following as physical or chemical changes:
melting of ice, burning of agarbatti, tearing of clothes, cooking of food, formation of clouds, formation of seeds from flowers, drying of wet clothes, formation of curd from milk, burning of cooking gas, dissolution of sugar in water, hammering of metals to form sheets, melting of wax, melting of butter, digestion of food, lightning in the sky, explosion of fire crackers.
- Change in colour
- Change in temprature
- Any one of all of these
- Evolution of gas
When a candle burns, both physical and chemical changes take place. Identify these changes. Give another example of a familiar process in which both the chemical and physical changes take place.
How will you justify that rusting of iron is a chemical change?
