Practice MCQ Questions and answers on Chemistry-GK

Human blood contains a buffer of carbonic acid (H₂CO₃) and bicarbonate anion (HCO₃^-) in order to maintain blood pH between 7.35 and 7.45, as a value higher than 7.8 or lower than 6.8 can lead to death. In this buffer, hydronium and bicarbonate anion are in equilibrium with carbonic acid. Furthermore, the carbonic acid in the first equilibrium can decompose into CO₂ gas and water, resulting in a second equilibrium system between carbonic acid and water. Because CO₂ is an important component of the blood buffer, its regulation in the body, as well as that of O₂ , is extremely important. The effect of this can be important when the human body is subjected to strenuous conditions.

Source : chem.libretexts.org

Bakelite is an early plastic. It is a thermosetting phenol formaldehyde resin, formed from an elimination reaction of phenol with formaldehyde.

Nylon is not an addition polymer.

Melamine formaldehyde resin is the polymer used for making plastic crockery. Its monomers are melamine and formaldehyde. Uses : It is used in making plastic (unbreakable) crockery.

Manufacture of poly(ethene) (polyethylene) Poly(ethene) is made by several methods by addition polymerization of ethene, which is principally produced by the cracking of ethane and propane, naphtha and gas oil.

Natural Rubber is a Polymer derived from Isoprene.

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

Polystyrene is an synthetic aromatic polymer made from the monomer styrene, a liquid petrochemical.

Viscose is a viscous organic liquid used to make rayon and cellophane. Viscose is also used as shorthand for Viscose Rayon, thus becoming synonymous with rayon, a soft man-made fibre commonly used in dresses, linings, shirts, shorts, coats, jackets, and other outer wear. It is also used in industrial yarns (tyre cord), upholstery and carpets. Viscose currently is becoming less common because of the polluting effects of carbon disulfide and other by-products of the process, forcing some factories to close. One way to comply with sulphur emission standards is to install a wet sulfuric acid process unit which recovers sulfur compounds to sulfuric acid or use the Lyocell process which uses N-Methylmorpholine N-oxide as solvent.

PVC, in full polyvinyl chloride, a synthetic resin made from the polymerization of vinyl chloride. Second only to polyethylene among the plastics in production and consumption, PVC is used in an enormous range of domestic and industrial products, from raincoats and shower curtains to window frames and indoor plumbing.