Advertisements
Advertisements
Question
Give a reason why – Heating a platinum wire is a reversible change but, heating a magnesium wire is an irreversible change.
Solution
Heating a platinum wire, the final product is again platinum wire (as platinum is a noble metal and does not react with air), i.e. no change in composition and is a physical change. Heating magnesium wire forms MgO i.e. composition changes a new substance white powder of magnesium oxide is formed is a chemical change.
APPEARS IN
RELATED QUESTIONS
Classify the following changes as physical or chemical:- photosynthesis in plants
State whether the following is physical or chemical changes.
glowing of a bulb -
State whether the following is physical or chemical changes.
growing of a piglet into a pig —
Write true or false
Melting of ice is a physical change.
Classify the following changes as physical or chemical.
Classify the following as a physical or a chemical change.
Melting of wax
Define a chemical change. Give two examples of the above changes.
Select the chemical changes from the following list of changes
Vaporisation of water into water vapour.
You are given some candle wax. Can you make a candle doll from it? What kind of change is this?
Classify the following as physical or chemical properties
Metallic sodium is soft enough to be cut with a knife.
