Chemistry
Assertion (A): Liquid ammonia is used as a refrigerant in ice plants.
Reason (R): CFC, the main refrigerant, causes global warming.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true but R is not the correct explanation of A.
Explanation — Liquid ammonia is used as a refrigerant in ice plants because anhydrous ammonia is a clear, colourless liquid under pressure. It evaporates rapidly and produces cooling effect. This makes ammonia a good refrigerant. Hence, the assertion (A) is true. CFC, the main refrigerant, decompose by ultraviolet rays to form free chlorine radicals. These free radicals contribute to global warming and ozone depletion. Hence, the reason (R) is true.
Since, reason (R) doesn't explain why liquid ammonia is used as refrigerant in ice plants, it is not the correct explanation of assertion (A).
Related Questions
Assertion (A): Haber's process is used to manufacture ammonia.
Reason (R): The catalyst used in this process is vanadium oxide or platinum.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): Ammonia is recovered by liquification process in Haber's process.
Reason (R): Nitrogen and hydrogen liquify with difficulty as compared to ammonia.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Name:
(a) the gas which is prepared by Haber's process.
(b) two gases which give dense white fumes with ammonia.
(c) one salt of ammonia in each case which is used in:
(i) dry cell (ii) explosives (iii) medicine(d) an acidic gas which reacts with a basic gas liberating a neutral gas,
(e) a metallic chloride soluble in ammonium hydroxide,
(f) the gas obtained when ammonia burns in an atmosphere of oxygen without any catalyst,
(g) a nitride of a divalent metal which reacts with warm water liberating ammonia,
(h) an amphoteric oxide reduced by the basic gas,
(i) a white salt produced by an acidic gas and a basic gas,
(j) The gas that burns in oxygen with a green flame.
(k) The gas produced when excess ammonia reacts with chlorine.
(l) The white crystalline solid that is soluble in water. It liberates a pungent smelling gas when heated with sodium hydroxide solution.
(m) An alkaline gas which produces dense white fumes when reacted with HCl gas.
Fill in the blank from the choices given in bracket :
(a) Ammonia gas is collected by ………….. (upward displacement of air, downward displacement of water, downward displacement of air).
(b) Ammonia reacts with excess chorine to form …………… (nitrogen / nitrogen trichloride / ammonium chloride).