NON-MEATALS, D. Acid, Base and Salt

51. The chemical used as fixer in the photography is – [U.P.R.O./A.R.O. (Pre) 2014]

(a) Sodium thiosulphate
(b) Borax
(c) Sodium tetrathionate
(d) Ammonium molybdate

Correct Answer: (a) Sodium thiosulphate

Solution:Sodium thiosulphate (Hypo) is used in photography as a fixer of positive and negative. It is also used in the extraction of Gold and Silver.

52. The hypo solution used in photography is an aqueous solution of – [U.P.P.C.S (Pre) 2010]

(a) Sodium thiosulphate
(b) Sodium tetrathionate
(c) Sodium sulphate
(d) Ammonium per sulphate

Correct Answer: (a) Sodium thiosulphate

Solution:Sodium thiosulphate (Hypo) is used in photography as a fixer of positive and negative. It is also used in the extraction of Gold and Silver.

53. The useful element in photography is – [U.P.P.C.S (Pre) 1992]

(a) Silver Nitrate
(b) Silver Bromide
(c) Sulphuric Acid
(d) Citric Acid

Correct Answer: (b) Silver Bromide

Solution:To develop the photographic plate, the plate is kept in the solution of silver bromide until all the silver bromide is dissolved.The light-sensitive material in traditional photographic film and paper is primarily composed of silver halides, most commonly Silver Bromide (AgBr), along with silver chloride (AgCl) and silver iodide (AgI). When light strikes these crystals, it initiates a chemical change that forms a latent image. Silver nitrate is a precursor but not the light-sensitive element itself in the emulsion.

54. Which one of the following is coated on the photographic plate? [U.P.P.C.S. (Mains) 2015]

(a) Silver oxide
(b) Silver bromide
(c) Silver chloride
(d) Silver iodide

Correct Answer: (b) Silver bromide

Solution:High resolution photographic plates have a coating of exceedingly fine-grained photosensitive emulsions with sub-microscopic crystals of silver bromide in gelatin.

55. Which one of the following substances is used in glazing the pottery? [U.P.P.C.S (Mains) 2015]

(a) Alum
(b) Calomel
(d) Zinc oxide
(d) Zinc oxide

Correct Answer: (d) Zinc oxide

Solution:

Zinc oxide is used in glazing the pottery. Here are some more oxides which are used in glazing - silicon dioxide, aluminium oxide, barium oxide, sodium oxide etc.

56. Which of the following imparts deep blue colour to glass? [U.P. RO/A.R.O. (Mains) 2017]

(a) Cobalt oxide
(b) Cupric oxide
(c) Ferric oxide
(d) Nickel oxide

Correct Answer: (a) Cobalt oxide

Solution:The coloured glass can be obtained by the addition of colouring ions. Cobalt oxide imparts deep blue colour to the glass. While cupric oxide and nickel oxide imparts black colour and ferric oxide imparts bluish-green glass.