Science Assertion & Reason

Assertion: A drop of petrol when touched with finger gives a chill feeling.
Reason: The above phenomenon is an endothermic one.

Assertion: The formation of iron oxide from iron is a chemical change.
Reason: For the rust to form from iron, it must be exposed to air and water.

Assertion: Burning of wood log to charcoal is a physical change.
Reason: The products formed of burning a piece of wood can be easily converted back to wood log.

Assertion: The process of conversion of liquid water to its vapours by heating the liquid is called boiling.
Reason: The process of conversion of water vapours to liquid by cooling the vapours is called condensation.

Assertion: The explosion of fire cracker is a physical change.
Reason: A physical change is a reversible change.

Assertion (A) : Cutting of paper into very small pieces is an irreversible change.
Reason (R) : Physical changes are always reversible.

Assertion (A) : No-new substance is formed when water is heated to get steam.
Reason (R) :Conversion of water into steam is a physical change.

Assertion (A) : Burning of a candle is considered a physical as well as chemical change.
Reason (R)Melting of wax is a physical change melted wax turns into vapours and then bums which is a chemical change.