An emulsion of sodium thiosulfate is called hypo by photographers. It is used to stop development of exposed film. Thiosulfate converts undeveloped silver bromide grains in the film into water-soluble silver thiosulfate complexes that can be removed when the film is washed.

Correct Option: A

An emulsion of sodium thiosulfate is called hypo by photographers. It is used to stop development of exposed film. Thiosulfate converts undeveloped silver bromide grains in the film into water-soluble silver thiosulfate complexes that can be removed when the film is washed.

Methane gas is a hydrocarbon gas largely composed of methane formed when organic material or vegetation decays in the absence of air. Naturally occurring methane is mainly produced by the process of methanogenesis. It is also known as Swamp Gas.

Correct Option: D

Methane gas is a hydrocarbon gas largely composed of methane formed when organic material or vegetation decays in the absence of air. Naturally occurring methane is mainly produced by the process of methanogenesis. It is also known as Swamp Gas.

The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961;Copper: 1083; Mercury: -38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.

Correct Option: C

The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961;Copper: 1083; Mercury: -38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.

All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H₂SO₄) to form a normal salt, Sodium Sulphate (Na₂SO₄). If only one atom of hydrogen is replaced by sodium, it forms an acid salt, Sodium Hydrogen Sulphate (NaHSO₄).

Correct Option: B

All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H₂SO₄) to form a normal salt, Sodium Sulphate (Na₂SO₄). If only one atom of hydrogen is replaced by sodium, it forms an acid salt, Sodium Hydrogen Sulphate (NaHSO₄).

Either the wording of the question is wrong or it doesn’t have a correct option. A non-conductor is a substance which does not allow the passage of electricity. As a general rule, all metals (Iron, Mercury, etc) are good conductors. Nonmetals are non-conductors, except for carbon in the form of graphite and the gas carbon. Copper Sulphate is a good electrolyte (a liquid which allows the passage of electricity. So all the options given in the question are good electrical conductors.

Correct Option: E

Either the wording of the question is wrong or it doesn’t have a correct option. A non-conductor is a substance which does not allow the passage of electricity. As a general rule, all metals (Iron, Mercury, etc) are good conductors. Nonmetals are non-conductors, except for carbon in the form of graphite and the gas carbon. Copper Sulphate is a good electrolyte (a liquid which allows the passage of electricity. So all the options given in the question are good electrical conductors.