Which one of the following statements regarding Bleaching powder and D.D.T. is correct?
- (a)Both are inorganic compounds
- (b)Both are organic compounds
- (c)Both contain chlorine
- (d)Both contain calcium
Correct — C, Both contain chlorine. Bleaching powder is calcium oxychloride, CaOCl2, and D.D.T. is dichlorodiphenyltrichloroethane, an organochlorine compound. The one property common to both is that each contains chlorine.
- (a)Both are inorganic compounds — Bleaching powder is inorganic, but D.D.T. is an organic (carbon-based) compound, so this is wrong.
- (b)Both are organic compounds — D.D.T. is organic, but bleaching powder is an inorganic salt of calcium, so this is wrong.
- (d)Both contain calcium — Bleaching powder contains calcium, but D.D.T. contains no calcium; only chlorine is common to both.
Bleaching powder is an inorganic salt, calcium oxychloride (CaOCl2), made by passing chlorine over dry slaked lime; it is an oxidising, bleaching and disinfecting agent. D.D.T. is an organochlorine insecticide, an organic molecule that is persistent and bioaccumulates in food chains. The two are very different in nature, and their single shared feature is the element chlorine.
Test each option element by element: only chlorine is present in both, while calcium is unique to bleaching powder, and the two differ in being inorganic versus organic.
- Bleaching powder is calcium oxychloride, CaOCl2, made by passing chlorine over dry slaked lime, Ca(OH)2.
- D.D.T. (dichlorodiphenyltrichloroethane) is an organochlorine insecticide; it is persistent and bioaccumulates.
- Both compounds contain chlorine, which is the only feature common to both.
- Bleaching powder is inorganic, whereas D.D.T. is organic.
Only chlorine is shared: bleaching powder is inorganic, D.D.T. is organic, and D.D.T. has no calcium.
- Assuming both are inorganic (D.D.T. is organic) or both organic (bleaching powder is inorganic).
- Picking calcium — only bleaching powder contains calcium.
Asked as the common feature of bleaching powder and D.D.T. — both are chlorine-containing compounds.
No directly related past PYQ was found.
- practice — not a real PYQ
Bleaching powder is chemically
- (a)calcium carbonate
- (b)calcium oxychloride
- (c)calcium hydroxide
- (d)calcium sulphate
Answer(b) calcium oxychloride, CaOCl2.
- practice — not a real PYQ
D.D.T. is best classified as
- (a)an inorganic salt
- (b)an organochlorine insecticide
- (c)a fertiliser
- (d)a natural indicator
Answer(b) an organochlorine insecticide.