261. 15th group is called ……. group:
(a) Carbon (b) Halogen
(c) Nitrogen (d) Oxygen
Answer: (c)
262. Halogens belong to ……. group.
(a) 15th (b) 16th
(c) 17th (d) 18th
Answer: (c)
263. Compound that does not form a clear solution with cold water is
Answer: Benzoic Acid
264. The lightest noble gas is
Answer: Helium
265. The light emitted during chemical reaction is called
Answer: chemiluminescence
266. Amber colour is imparted to glass by adding
Answer: carbon
267. Simpson and Harrison are associated with the invention of
Answer: Chloroform
268. Epsom salt is
Answer: hydrated magnesium sulphate
269. Penicillin was invented by Fleming in the year
Answer:1929
270. The salt is known as ‘Pearl ash’ is-
Answer: Potassium carbonate
271. The National Chemical Laboratory is situated in
– Pune
272. PVC plastics are obtained from vinyl chloride by the process of
– polymerization
273. Milk is an example of
– emulsion
274. The boiling point of water, on the kelvin scale of temperature, is
– 373
275. The substance that causes the worst air pollution is
– carbon monoxide
276. Dolomite is an ore of
-Mg
277. The element used in photocopying machines is
– Selenium
278. In breeder reactors, uranium-238 is converted into
– Plutonium-239
279. The process of elimination of water from any system is called.
– dehydration
280. Chemotherapy deals with
– The study and uses of chemicals in the cure of diseases.
281. The point at which the solid, liquid and gaseous forms of a substance co-exist is called its
– triple point
282. The IC chips used in computers are made of
– Silicon
283. For rural electrification and domestic cooking, most appropriate and economical would be
– biogas
284. The full form of D.D.T.:
Dichlorodiphenyltrichloroethane
285. The acid contained palm oil:
Palmitic acid
286. Vinegar contains:
(a) Acetic acid (b) Lactic acid
(c) Malic acid (d) Citric acid
Answer: (a)
287. The acid contained in gastric juice:
(a) Prussic acid (b) Ascorbic acid
(c) Hydrochloric acid (d) Tartaric acid
Answer: (c)
288. What is known as the king of chemicals?
(a) Hydrochloric acid (b) Sulphuric acid
(c) Nitric acid (d) Acetic acid
Answer: (b)
289. The acid used for quick solidification of rubber latex:
(a) Lactic acid (b) Acetic acid
(c) Formic acid (d) Sulphuric acid
Answer: (c)
290. The acid contained in Grapes:
(a) Tartaric acid (b) Lactic acid
(c) Citric acid (d) Urine-Uric acid
Answer: (a)