Electron affinity is maximum for
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Solution
Electron affinity is energy released when electron is added to isolated gaseous atom. Its value decreases down the group. So electron affinity of F should be highest among halogens but due to its smaller size electron affinity of Cl is more than F.
∴ Cl has highest electron affinity.
Electron affinity is positive when :
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Solution
Electron affinity is said to be positive when an atom has spontaneous tendency to accept an electron. When O changes to O–, energy is released. So, this change has positive electron affinity while all other given changes required to be forced i.e., these require energy to occur.
A group 16 element exists in the monoatomic state in the metallic state. It also exists in two crystalline forms. The metal is
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Solution
Pollonium is only true metal in group 16. It has two crystalline forms ?-form which is cubic and ?-form which is rhombohedral.
Which one of the following represents the electronic configuration of the most electropositive element ?
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Solution
Electropositive nature increases down the group and decreases across the period.
The correct order of reactivity of halogens is
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Solution
We know that atomic no. of fluorine (F), chlorine (Cl)Bromine (Br) and Iodine (I) are 9, 17, 35 and 53 respectively. Therefore, correct order of reactivity of halogens is F >Cl > Br > I.
Eka-aluminium and EKa-silicon are known as
As per the modern periodic law,the physical and chemical properties of elements are periodic functions of their
Among the following options, the sequence of increasing first ionisation potential will be
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Solution
1st l.P. increases from left to right in a period.
Arrange S, P, As in order of increasing ionisation energy
Which ionisation potential (IP)in the following equations involves the greatest amount of energy ?
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Solution
k+ → k2 + e-. Since e –is to be removed from stable configuration.