(a)   glucose
     (b)   fructose
     (c)   sucrose
     (d)   maltose
Ans: (a)
257. Fructose is also called
     (a) dextrose
     (b) fruit sugar
     (c) beet sugar
     (d) blood sugar
Ans: (b)
258. The sugar which is used in silvering mirrors is
     (a) sucrose
     (b) maltose
     (c) glucose
     (d) fructose
Ans: (c)
259. Mortar contains cement and sand in the ratio of
     (a) 1 : 1
     (b) 1 : 2
     (c) 2 : 3
     (d) 1 : 3
Ans: (d)
260. Flint glass contains
     (a) potassium and lead silicates
     (b) zinc and barium borosilicates
     (c) potassium and calcium silicates
     (d) sodium and calcium silicates
Ans: (a)
261. The raw materials required for the manufacture of glass are
     (a) silica, sodium nitrate and soda ash
     (b) silica, limestone and sodium nitrate
     (c) silica, sodium oxide and limestone
     (d) silica, soda ash and limestone
Ans: (d)
262. Optical instruments are made of
     (a) pyrex glass
     (b) flint glass
     (c) quartz glass
     (d) Crooke"s glass
Ans: (c)
263. Glass articles are annealed so that
     (a) they may appear better
     (b) they can resist the action of acids and alkalies
     (c) they lose their brittleness
     (d) they can withstand temperature shocks
Ans: (c)