GK-Chemistry Question and Answer
GK-Chemistry Question and Answer
31. The mass of one Avogadro number of helium atom is
- 1.00 gram
- 4.00 gram
- 8.00 gram
- 4 x 6.02 x 1023 gram
32. The items amenable to detection by soft x-rays are
- contrabands
- lead in bullets
- narcotics
- genuine coins from counterfeit coins
33. The material which can be deformed permanently by heat and pressure is called a
- thermoplastic
- thermoset
- chemical compound
- polymer
34. The mass number of a nucleus is
- always less than its atomic number
- the sum of the number of protons and neutrons present in the nucleus
- always more than the atomic weight
- a fraction
35. The inexpensive and commonly used variety of glass is called soda glass. It is called so
because
because
- was used initially for making bottles of soda(carbonated drink)
- is made using soda(sodium carbonate)
- was initially used for storing sodium carbonate
- is made using soda lime
36. The gas used in the manufacture of vanaspati from vegetable oil is
- hydrogen
- oxygen
- nitrogen
- carbon dioxide
37. The graphite rods in the nuclear reactor
- react with U to release energy
- produce neutrons
- undergo combustion which triggers the nuclear fission
- convert fast moving neutrons into thermal neutrons
40. The method that cannot be used for removing permanent hardness of water is
- adding sodium carbonate
- distillation
- adding caustic soda
- boiling