Question

Borax (sodium tetraborate) has many uses, some of which are mentioned here, except?
(A) For giving a glaze to linen, in laundering
(B) In bleaching of paper pulp
(C) Making heat-resistant
(D) As a flux in welding and soldering

Answer 1

Borax is also known as sodium borate, sodium tetraborate or disodium tetraborate. It is a colorless crystalline solid that dissolves in water. It is used in cleaning, fire retardants, glazing and also in welding.

Complete step by step solution:
In nature, borax combines to form boric acid and inorganic salts called borates. Borax is a form of hydrous sodium borate which occurs naturally in the region where evaporation of saline lake takes place.
Borax is a component of many daily life products like detergents, cosmetics and enamel glazes. Borax is used to make a buffer solution, it is used as a fire retardant, it is also used as an antifungal compound. Borax is used in manufacturing of fiberglass and as a flux in metallurgy. Borax is used as a neutron-capture shield for radioactive sources. It gives a good texture agent, therefore used in cooking. It is used in developing photographs. It is used as an alkali while developing photographs. It is also used as an insecticide. In artisanal gold mining, borax is used as a part of a process of eliminating the toxic mercury in the gold extraction process. Borax is used and added in flame to give it a yellow green color.
Borax is used for many cleaning purposes and can be used to make homemade laundry detergent. It even keeps ants and other pests away. It is also used as a flux in soldering and welding. Borax is not used in bleaching of paper pulp.
Therefore, the correct answer is option B.

Note:
Borax is converted into boric acid or borates which have many other different applications. It is toxic and can cause organ damage or poisoning.