GK Quiz 005 on Chemistry

pH of blood is ?

A pH of 7 is neutral. The lower the pH, the more acidic the blood. A variety of factors affect blood pH including what is ingested, vomiting, diarrhea, lung function, endocrine function, kidney function, and urinary tract infection. The normal blood pH is tightly regulated between 7.35 and 7.45.

Who proposed first atomic theory ?

Democritus first suggested the existence of the atom but it took almost two millennia before the atom was placed on a solid foothold as a fundamental chemical object by John Dalton (1766-1844). Although two centuries old, Dalton's atomic theory remains valid in modern chemical thought.

What among following is used to produce artificial rain ?

The most common chemicals used for cloud seeding include silver iodide, potassium iodide and dry ice (solid carbon dioxide).

Natural rubber is the polymer of :

Natural rubber, also called India rubber or caoutchouc, as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds, plus water.

An electric iron has a heating element made of :

Most heating elements use nichrome 80/20 (80% nickel, 20% chromium) wire, ribbon, or strip. Nichrome 80/20 is an ideal material, because it has relatively high resistance and forms an adherent layer of chromium oxide when it is heated for the first time.