Advertisements
Advertisements
प्रश्न
Which of the following are chemical changes?
(i) Decaying of wood
(ii) Burning of wood
(iii) Sawing of wood
(iv) Hammering of a nail into a piece of wood
पर्याय
(i) and (ii)
(ii) and (iii)
(iii) and (iv)
(i) and (iv)
उत्तर
(i) and (ii)
Explanation:
Decaying of wood and burning of wood are chemical changes since there is a change in the chemical composition of wood. Sawing of wood and hammering of a nail into a piece of wood are physical changes since there is no change in the composition of the wood during these changes.
APPEARS IN
संबंधित प्रश्न
Complete and balance the following chemical equations:
Zn + `"H"_2"SO"_4` `→`
(dil)
FILL IN THE BLANK
On reaction with sulphuric acid solution, barium chloride forms a white precipitate of ........ sulphate.
Give an example of a reaction where the following are involved
Electricity
Give an example of a reaction where the following are involved
Pressure
Define:
Electrochemical reaction
Give one example
Explain the term ‘chemical reaction’ with special reference to – ‘reactants’ and ‘products’.
State the following reaction represent oxidation or reduction.
\[\ce{H->H+}\]
Explain the term chemical reaction with special reference to reactants and products.
Analogy:
H2O: Water:: NaCl: ______.
Write a note on the catalyst.
