Practice MCQ Questions and answers on Chemistry-GK

Synthetic detergents are prepared from hydrocarbons of petroleum. They are sodium salts of a long chain benzene sulphonic acids or sodium salts of long chain alkyl hydrogen sulphates. Calcium and magnesium salts of detergents are soluble in water. Therefore cleansing action of detergents remain unaffected in hard water.

Gun powder is the mixture of potassium nitrate powdered charcoal and sulphur.

Iodex has the characteristic odour of Methyl salicylate, an organic ester naturally produced by many species of plants, particularly wintergreens. It is used in high concentrations as a rubefacient and analgesic in deep heating liniments to treat joint and muscular pain.

Silver halides are used in photography because they are photosensitive as they react with light to form the image, silver halides being reduced to silver. They are also soluble in hyposolution.

Edward Teller, Stanislaw M. Ulam, and other American scientists developed the first hydrogen bomb, which was tested at Enewetak atoll on November 1, 1952.

Synthetic detergents are made from sodium salt of benezene sulphonic acid.

Commonly used antiseptic, dettol is a mixture of chloroxylenol and terpineol.

Ethylene gas, acetylene gas liberated from calcium carbide, and ethephon are some of the commercial ripening agents used successfully in the trade and they have been widely studied for their effectiveness on initiating and accelerating the ripening process and their effect on fruit quality and health related issues.

Common refrigerants used in domestic refrigerators are freon, neon and nitrogen. It flows through four components of refrigerator again and again. These four components are cooling chamber, compressor, heat exchanger and expander.

Embalming fluids use formaldehyde as a preservative. Formaldehyde is the simplest aldehyde with the chemical formula HCHO. Formalin is a solution of formaldehyde in water, usually with a small amount of methanol added. It is widely used as an antiseptic, disinfectant and preservative for biological materials.