A. Stone bed method
B. biofilter method
C. aerobic filtration
D. anerobic filtration
✅ The correct answer is option B.
SSC
622. Which among the following is the most important characteristic of Noble metals?
A. Luster
B. Non reactive nature
C. Preciousness
D. Rare availability
✅ The correct answer is option B.
623. Adsorption is used commonly in which of the following processes?
A. Purification of solids
B. Purification of liquids
C. Making scrubbers
D. Chromatography
✅ The correct answer is option D.
624. An Jewellery was left exposed to the atmosphere for some time and it becomes coated with green carbonate. The Jewellery is made up of which of the following?
A. Copper
B. Silver
C. Zinc
D. Gold
✅ The correct answer is option A.
625. Which among the following gas is used in Balloons?
A. Hydrogen
B. Helium
C. Nitrogen
D. Oxygen
✅ The correct answer is option B.
626. In which of the following Mercury is a constituent?
A. Cinnabar
B. Chile saltpeter
C. Calamine
D. Gold
✅ The correct answer is option A.
627. When we buy a Jewellery of 22 carat Gold , this means that we are getting a purity of gold with ______?
A. 90%
B. 91.67%
C. 95.5%
D. 98%
✅ The correct answer is option B.
628. Charles Goodyear is known for which of the following?
A. Experiments on Rubber Plants
B. Vulcanization of Rubber
C. Invention of Radial Tyres
D. Invention of Artificial Rubber
✅ The correct answer is option B.
629. Calamine lotion which is used as an antipruritic (anti-itching agent) to treat mild pruritic conditions contains which of the following?
A. Zinc
B. Calcium
C. Magnesium
D. Sodium
✅ The correct answer is option A.
630. The atomic weight of Chlorine is 35. It consists of _______?
A. 17 Protons + 18 Neutrons
B. 17 Neutrons + 18 protons
C. 17 Neutrons + 17 Protons + 1 electron
D. None of the above
✅ The correct answer is option A.