Chemistry - Study Mode
[#351] Total number of halogen elements found in the periodic table is
Correct Answer
(B) 5
Explanation
Solution: Total number of halogen elements found in the periodic table is 6.
[#352] Ionisation energy of nitrogen is greater than that of oxygen because nitrogen has
Correct Answer
(C) Stable half filled 2p sub level
Explanation
Solution: Nitrogen has a half filled orbital. On the other hand, since Oxygen is already unstable relative to Nitrogen, by losing one electron it attains a stable half filled orbital. So oxygen undergoes ionisation at a relatively lower energy. This is why nitrogen has a higher ionisation energy than oxygen.
[#353] The elements with atomic numbers 9, 17, 35, 53, 85 are all
Correct Answer
(D) Halogens
Explanation
Solution: Halogens are the elements which belong to Group 17 of the periodic table. The atomic number of the elements present in this group are 9, 17, 35, 53 and 85. The elements are Fluorine, Chlorine, Bromine, Iodine and Astatine.
[#354] The natural resource, known as black gold is
Correct Answer
(A) Coal
Explanation
Solution: The term "coal is a black gold" is just a simple metaphor. Even today, we burn more coal than natural gas, more than nuclear, more than anything.
[#355] The chief constituent of natural gas is:
Correct Answer
(A) Methane
Explanation
Solution: Naturally occurring mixture of a hydrocarbon gas with methane being the primary constituent is called natural gas. Other gases found in minute traces are hydrogen, hydrogen sulphide, nitrogen, carbon monoxide and carbon dioxide.