CHEMISTRY

CHEMISTRY

Sainul Abid


1. Which element has the lowest melting point?

Ans:- Helium


2. The element with the highest densi-111:

Ans:- Osmium


3. The lightest metal:

Ans:- Lithium


4. The element with the highest boiling point:

Ans:- Tungsten


5. The most abundant elements in the Sun in the correct order:

Ans:- H,He,O


6. Which element has the second highest density?

Ans:- Iridium


7. The most abundant metal in human body:

Ans:- Calcium


8. What percent of the atmosphere is Oxygen?

Ans:- 20.95


9. What percent of the mass of human body is Oxygen?

Ans:- 65


10. Select the correct order of abundance in the atmosphere:

Ans:- N,O,Ar,CO2


11. The most common element on the earth's crust by mass:

Ans:- Oxygen


12. The most abundant element in the moon:

Ans:- Oxygen


13. Which metal has the highest melting point?

Ans:- Tungsten


14. The most abundant metal in Earth:

Ans:- Iron


15. The element with atomic number 100:

Ans:- Fermium 


16. Water has maximum density at ______ degree Celsius:

Ans:- 4


17. The gas using for filling balloons:

Ans:- Helium


18. Beryllium aluminum silicate is known as:

Ans:- Emerald


19. The isotope using for radio carbon dating:

Ans:- Carbon-14


20. Which is not correctly matched?

Ans:- Helium-Chemical sun


21. The best non-metallic conductor of electricity:

Ans:- Graphite


22. The first Trans Uranic element:

Ans:- Neptunium


23. Most chemically reactive element?

Ans:- Flourine


24. The colour of sodium vapour lamp:

Ans:- Yellow


25. The essential constituent chlorophyll:

Ans:- Magnisium


26. The first to isolate aluminium from bauxite:

Ans:- Charles Martin Hall


27. The main constituent of bone:

Ans:- Calcium phosphate


28. Which is used for the vulcanisation of rubber:

Ans:- Sulpher


29. The most abundant inert gas:

Ans:- Argon


30. Which is known as the 'metal of future'?

Ans:- Titanium 


31.Galvanisation is the process of coating of on other metals.

Ans:- Zinc


32. What is known as the ling of poi-sons'?

Ans:- Arsenic


33. What is used in fire works for red flame?

Ans:- Strontium


34. The first element that was produced artificially:

Ans:- Technitium


35. Chemical used for artificial rain:

Ans:- Silver iodide


36. The rarest metal:

Ans:- Rhodium


37. The best conductor of heat and electricity:

Ans:- Silver


38. The most electropositive stable element:

Ans:- Caesium


39. Barium imparts _____ colour to flames:

Ans:- Green


40. What is known as 'little silver'?

Ans:- Platinum


41. What is used as an X ray radio contrast agent?

Ans:- Barium


42. Semi conductor used for making integrated circuits:

Ans:- Germanium.


43. Number of Hydrogen atoms in a water molecule:

Ans:- 2


44. The only substance in exists in nature in three three forms- solid, liquid and gas:

Ans:- Water


45. Atomic number of Carbon:

Ans:- 6


46. Which is known as 'universal sol-vent'?

Ans:- Water


47. The total number of natural elements:

Ans:- 92


48. The poisonous gas emited from the engines of two wheelers:

Ans:- Carbon Monoxide


49. Gas filled in the tyres of aeroplanes:

Ans:- Helium I


50. The pH value of water:

Ans:- 7


51. Element which is used in Torch cell:

Ans:- Zinc


52. Non metal element present in liq-uid state:

Ans:- Bromine


53. Purest form of water:

Ans:- Rain water


54. Water has minimum density at _____ degree Celsius.

Ans:- 0


55. The most abundant salt in sea water:

Ans:- Sodium chloride


56. Colour of hydrogen gas:

Ans:- Colourless


57. Water is known as:

Ans:- Blue gold


58. Which is known as 'Chemical Sun'?

Ans:- Magnisium


59. Which is known as 'Yellow Cake'?

Ans:- Uranium oxide


60. Element formed during hydrogen bomb explosion:

Ans:- Helium


61. Which symbol is incorrect?

Ans:- Potassium-P


62. Ozone is a/an _____:

Ans:- Element


63. Nucleon is:

Ans:- Neutron+Proton


64. Element present in DNA and RNA:

Ans:- Phosphorus


65. Element present in all explosives:

Ans:- Nitrogen


66. Ithai-Ithai disease is caused by:

Ans:- Cadmium


67. Which element. has the name with the meaning 'stranger'?

Ans:- Xenon


68. Sweetest natural sugar:

Ans:- Fructose


69. Colour of chlorine vapour lamp:

Ans:- Green


70. The chemical that causes acid rain:

Ans:- Sulphur dioxide


71. Phenol is also known as:

Ans:- Carbolic acid