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The first (DeltaiH1) and the second (Del...

The first `(Delta_iH_1)` and the second `(Delta_iH_2)` ionisation enthalpies in `"kJmol"^(-1)` and the electron gain enthalpy `(Delta_(eg)H)` in `"kJmol"^(-1)` of a few elements are given below:
`{:("Elements",Delta_iH_1,Delta_iH_2,Delta_(eg)H),("(P)",520,7300,-60),("(Q)",419,3051,-48),("(R)",1681,3374,-328),("(S)",1008,1846,-295),("(T)",2372,5251,+48),("(U)",738,1451,-40):}`
Which one of the above elements is least reactive?

A

(R)

B

(S)

C

(T)

D

(U)

Text Solution

Verified by Experts

The correct Answer is:
C
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The first (DletaH) and second ionisation enthalipies (DeltaH_(2)) in kJmol^(-1) and the electron gain enthalpy (DeltaHg) in kJmol^(-1) of a few elements are given below: Which element is likely a) the least reactive element c) the most reactive non-metal b) the most reactive metal d) the least reactive non-metal f) the metal which can form a predominantly stable covalent halide of the formula MX.

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