Chemistry - Environmental Chemistry Question with Solution | TestHub
Number of correct statements among the following are.
(A) Classical smog is mixture of smoke + fog
(B) Photochemical smog leads to cracking of rubber
(C) The value of concentration of B.O.D. (Biological oxygen demand) of clean water and highly polluted water is less than 5 ppm and more than 17 ppm
(D) Aq. NaOH solution is used in Bayer's process for concentration of Red Bauxite
(E) BeO is purely acidic in nature
(F) Barium salts impart apple green colour in Flame test
(G) H-H bond dissociation energy is more than bond energy
Answer:
Solution:
(A) Correct → Classical smog contains smoke + fog + SO₂.
(B) Correct → Photochemical smog damages and cracks rubber.
(C) Correct → Clean water has BOD < 5 ppm, polluted water > 17 ppm.
(D) Correct → Aqueous NaOH is used in Bayer’s process for red bauxite.
(E) Incorrect → BeO is amphoteric, not purely acidic.
(F) Correct → Barium salts give apple green colour in flame test.
(G) Correct → H–H bond dissociation energy is greater than C–C bond energy.