Advertisements
Advertisements
प्रश्न
Which of the following are chemical changes ?
- decaying of wood
- burning of wood
- sawing of wood
- hammering of nail into wood
विकल्प
(i) and (ii)
(ii) and (iii)
(iii) and (iv)
(i) and (iv)
Advertisements
उत्तर
(i) and (ii)
The processes in statements (i) and (ii) are chemical changes because decaying and burning causes formation of new compounds; thus they are chemical reactions. The processes in statements (iii) and (iv) are physical changes where no new compounds are formed.
APPEARS IN
संबंधित प्रश्न
Classify the following as chemical or physical change:
Making a fruit salad with raw fruits
Classify the following as chemical or physical change:
Burning of paper and wood
Write short answer.
What are man-made changes ?
Classify the following changes as physical or chemical: curdling of milk
State the various conditions that favour the process of evaporation.
Write true or false
Melting of ice is a physical change.
The rusting of an iron object is called :
Differentiate between a physical change and a chemical change with reference to – Nature of change is temporary and reversible or permanent and irreversible.
Explain the term – ‘sublimation’. Is sublimation of naphthalene – a physical or a chemical change. Give reasons.
Fill in the blank with the correct word of the statement given below:
Sublimation involves a __________ change.
