GK-General Science Question and Answer
GK-General Science Question and Answer
21. Among the various allotropes of carbon,
- coke is the hardest, graphite is the softest
- diamond is the hardest, coke is the softest
- diamond is the hardest, graphite is the softest
- diamond is the hardest, lamp black is the softest
22. The group of metals Fe, Co, Ni may best called as
- transition metals
- main group metals
- alkali metals
- rare metals
24. The chemical (ethyl merceptan) added to the otherwise odourless LPG cooking gas for
imparting a detectable smell to the gas is a compound of
imparting a detectable smell to the gas is a compound of
- bromine
- fluorine
- chlorine
- sulphur
28. Carbon, diamond and graphite are together called
- allotropes
- isomers
- isomorphs
- isotopes
30. Permanent hardness of water may be removed by the addition of
- sodium carbonate
- alum
- potassium permanganate
- lime