NON-MEATALS, D. Acid, Base and Salt

Total Questions: 56

41. Table salt (NaCl) is a product of – [53rd to 55th B.P.S.C. (Pre) 2011]

(a) Weak acid and weak base
(b) Strong acid and strong base
(c) Weak acid and strong base
(d) Strong acid and weak base

Correct Answer: (b) Strong acid and strong base

Solution:The compounds formed after the reaction between the strong base and strong acid are known as neutral salt. Sodium chloride (NaCl) is an example of neutral salt, which is also known as Table Salt.

42. Which one of the following salts should not be used as dining table salt? [U.P. RO/A.R.O. (Pre) 2014]

(a) Iodized salt
(b) Sea salt
(c) Rock salt
(d) Processed common salt
(e) None of the above

Correct Answer: (e) None of the above

Solution:According to the question, all the four above-mentioned salts can be used as table salt. Sea salt, rock salt, and table salt contain around 100% sodium chloride, which means that too much of any of them will have a negative effect on your health. Sea salt and rock salt are often marketed as being a healthier or tastier option than table salt but can be considerably more expensive.

43. Iodised salt contains : [60th to 62nd B.P.S.C. (Pre) 2016]

(a) Free iodine
(b) Calcium iodide
(c) Magnesium iodide
(d) Potassium iodide
(e) None of the above/More than one of the above

Correct Answer: (d) Potassium iodide

Solution:Potassium iodide (KI) is similar to food salt in the structure and physical properties. This is commonly used in making iodised salt. In addition to potassium iodide, sodium iodide and sodium iodate are also used in making iodised salt.

44. Which one of the following statements is not correct? [I.A.S. (Pre) 2003]

(a) The presence of NaCl increases the rate of setting of Plaster of Paris
(b) Gypsum is added to the cement to slow down its rate of setting
(c) All alkaline earth metals form hydrated salts
(d) Barium and Strontium are found free in nature

Correct Answer: (d) Barium and Strontium are found free in nature

Solution:Barium (Ba) and Strontium (Sr) are not found in nature as free element. These two belong to group 2 of the periodic table. The metals of this particular group are highly reactive. As a result of which, when they come into contact with the atmosphere, they form compounds.

45. What is untrue for bleaching powder? [39th B.P.S.C. (Pre) 1994]

(a) It is more soluble in water
(b) It is powder of light yellow colour
(c) It is an oxidant
(d) It releases chlorine after reaction with dilute acid

Correct Answer: (a) It is more soluble in water

Solution:Calcium Hypochlorite or Calcium Oxychloride is an inorganic compound. It is also known as bleaching powder. Its chemical formula is Ca(OCl)Cl. It is a white solid, although commercial samples appear yellow. It is an oxidizing agent and releases chlorine after reaction with dilute acid. Bleaching powder is used for water treatment and acts as a bleaching agent. It is not highly soluble in water.

46. Which chemical compound is present in Bleaching Powder? [U.P.U.D.A./L.D.A. (Spl.) (Mains) 2010]

(a) Calcium Hydroxide
(b) Calcium Oxychloride
(c) Calcium Carbonate
(d) Ammonium Chloride

Correct Answer: (b) Calcium Oxychloride

47. When eno salt is poured into the water, bubbles form, which is due to – [R.A.S./R.T.S. (Pre) 1999]

(a) O₂ gas
(b) CO₂ gas
(c) CO gas
(d) H₂ gas

Correct Answer: (b) CO₂ gas

Solution:When eno salt is dissolved in water, the carbon dioxide gas is produced which produces gas bubbles.

48. To develop photographic plates – [R.A.S./R.T.S. (Pre) 1994]

(a) Sodium thiosulphate is used as oxidising agent.
(b) Free bromine releases.
(c) Light affected area quickly oxidizes.
(d) The solution is kept developing until all the bromide is not dissolved.

Correct Answer: (a) Sodium thiosulphate is used as oxidising agent.

Solution:Sodium thiosulphate is used in photographic processing as a fixer in photography. Sodium thiosulphate removed Silver Bromide as a soluble compound from the negative plate or film which is obtained at the end of photographic development. It is used as oxidizing agent.

49. Which one of the following substances is used in photography and also as an antichlor? [U.P.P.C.S. (Mains) 2016]

(a) Chrome red
(b) Sodium thiosulphate
(c) Hydrogen peroxide
(d) Calomel

Correct Answer: (b) Sodium thiosulphate

Solution:Sodium thiosulphate (Hypo) is a colourless crystalline substance. It is used in photography and also as an antichlor. An antichlor is a substance used to decompose residual hypochlorite or chlorine after chlorine-based bleaching.

50. The chemical used as a 'fixer' in photography is – [I.A.S. (Pre) 1995]

(a) Sodium sulphate
(b) Sodium thiosulphate
(c) Ammonium persulphate
(d) Borax