The first - H1 and second - H2 ionisation enthalpies in kJ mol-1 and the - egH electron gain enthalpy in kJ mol-1 of a few elements are given below- Elements -1H1 -1H2 -egHA P 520 7300 -60B Q 419 3051 -48C R 1681 3374 -328D S 1008 1846 -295E T 2372 5251 -48F U 738 1451 -40The most reactive metal is -

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Byju's Answer

Standard XIII

Chemistry

Ionization Enthalpy

The first Δ H...

Question

The first ( $Δ H_{1}$ ) and second ( $Δ H_{2}$ ) ionisation enthalpies (in kJ $m o l^{- 1}$ ) and the ( $Δ_{e g} H$ ) electron gain enthalpy (in kJ $m o l^{- 1}$ ) of a few elements are given below:
Elements $Δ_{1} H_{1}$ $Δ_{1} H_{2}$ $Δ_{e g} H$
(A) P 520 7300 -60
(B) Q 419 3051 -48
(C) R 1681 3374 -328
(D) S 1008 1846 -295
(E) T 2372 5251 +48
(F) U 738 1451 -40
The most reactive metal is :

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Solution

The correct option is B Q
Metal having low $I E_{1}$ and higher $I E_{2}$ corresponds to alkali metal. Hence, Q is most reactive metal (easily forms cation).

Suggest Corrections

Similar questions

Q. The first and the second ionisation enthalpies in

k J m o l^{- 1}

and the electron gain enthalpy in

k J m o l^{- 1}

of a few elements are given below:

\begin{matrix} Elements & Δ_{i} H_{1} & Δ_{i} H_{2} & Δ_{e g} H (A) & 520 & 7300 & - 60 (B) & 419 & 3051 & - 48 (C) & 1681 & 3374 & - 328 (D) & 1008 & 1846 & - 295 (E) & 2372 & 5251 & + 48 (F) & 738 & 1451 & - 40 \end{matrix}

Which one of the above elements is least reactive?

Match the correct ionization enthalpies and electron gain enthalpies of the following elements.

List I	List II
A. Most reactive non-metal	1. $Δ H_{1} = 419, Δ H_{2} = 3051, Δ_{e g} H = - 48$
B. Most reactive metal	2. $Δ H_{1} = 1681, Δ H_{2} = 3374, Δ_{e g} H = - 328$
C. Least reactive elements	3. $Δ H_{1} = 738, Δ H_{2} = 1451, Δ_{e g} H = - 40$
D. Metal forming binary halide	4. $Δ H_{1} = 3272, Δ H_{2} = 5251, Δ_{e g} H = + 48$

Q. The first (

Δ H_{1}

) and second (

Δ H_{2}

) ionisation enthalpies (in kJ

m o l^{- 1}

) and the (

Δ_{e g} H

) electron gain enthalpy (in kJ

m o l^{- 1}

) of a few elements are given below:
Elements

Δ_{1} H_{1}

Δ_{1} H_{2}

Δ_{e g} H

(A) P 520 7300 -60
(B) Q 419 3051 -48
(C) R 1681 3374 -328
(D) S 1008 1846 -295
(E) T 2372 5251 +48
(F) U 738 1451 -40
The most reactive metal is :

Match the corect ionisation enthalpies and electron gain enthalpies of the following elements.
$\begin{matrix} E l e m e n t s & △ H_{1} & △ H_{2} & △_{e g} H (i) & M o s t r e a c t i v e n o n m e t a l & A & 419 & 3051 & - 48 (i i) & M o s t r e a c t i v e m e t a l & B & 1681 & 3374 & - 328 (i i i) & L e a s t r e a c t i v e e l e m e n t & C & 738 & 1451 & - 40 (i v) & M e t a l f o r m i n g b i n a r y h a l i d e & D . & 2372 & 5251 & + 48 \end{matrix}$