Chemistry
Select the correct answer from the choice in bracket to complete each sentence:
A change in which a substance retains its identity is a …………… [physical/chemical] change.
Matter is added or removed during a …………… [chemical/physical] change.
Energy required for completion of a physical change is …………… [released/absorbed] when the change is reversed.
Dissolution of lead nitrate in water is deemed as a …………… [physical/chemical] change.
A change in which matter undergoes a change but the total mass of substance is unaltered is a …………… [physical/chemical] change.
Phy & Chem Changes
30 Likes
Answer
A change in which a substance retains its identity is a physical change.
Matter is added or removed during a chemical change.
Energy required for completion of a physical change is released when the change is reversed.
Dissolution of lead nitrate in water is deemed as a physical change.
A change in which matter undergoes a change but the total mass of substance is unaltered is a physical change.
Answered By
14 Likes
Related Questions
Give a reason why —
(a) Heating a platinum wire is a reversible change but, heating a magnesium wire is an irreversible change.
(b) Addition of zinc nitrate to water is a physical change but, addition of zinc to dilute nitric acid is a chemical change.
(c) Rusting of iron is a chemical change but, magnetization of iron is a physical change.
Select the chemical changes from the following list of changes -
(a) Vaporisation of water into water vapour
(b) Boiling of milk
(c) Respiration in mammals
(d) Rotting of eggs
(e) Drying of a fruit
(f) The carbon cycle
(g) Occurrence of lightening
(h) Breaking of glass
(i) Butter turning rancid
(j) Glowing of an electric bulb
(k) Crystallisation of a salt from its solution
(l) Change of seasons
(m) Preparation of carbon dioxide from calcium carbonate & dilute hydrochloric acid
State which of the following 1 to 5 pertain to —
A: Physical Change
B: Chemical change
Sublimation.
Fermentation.
Liquefaction or condensation.
Magnetization.
Respiration.
Give reasons why the following are considered as chemical changes.
Copper carbonate on heat gives copper oxide and carbon dioxide.
A bright light is seen evolved when a strip of magnesium is heated.
Sulphur when burnt in air evolves a gaseous acidic product.
An iron nail kept open in the atmosphere rusts.
A piece of magnesium strip is dropped into a beaker containing dilute hydrochloric acid.