Why is the first ionisation enthalpy of Cr lo | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The first ionisation enthalpy depends on the effective nuclear charge and the electronic configuration of the atom.$Cr$ has the electronic configu

Vedclass · Accepted Answer

$Cr$ has a stable $d^5$ configuration,while $Zn$ has a stable $d^{10}$ configuration.

Vedclass · Answer

(A) The first ionisation enthalpy depends on the effective nuclear charge and the electronic configuration of the atom.$Cr$ has the electronic configuration $[Ar] 3d^5 4s^1$.$Zn$ has the electronic configuration $[Ar] 3d^{10} 4s^2$.Although $Cr$ has a stable half-filled $d$-subshell,the effective nuclear charge of $Zn$ $(Z=30)$ is significantly higher than that of $Cr$ $(Z=24)$.As the atomic number increases across the $3d$ series,the effective nuclear charge increases,which pulls the electrons closer to the nucleus,making them harder to remove.Therefore,the first ionisation enthalpy of $Zn$ is higher than that of $Cr$ due to its higher effective nuclear charge and the stability of the completely filled $d^{10}$ subshell.

Why is the first ionisation enthalpy of $Cr$ lower than that of $Zn$?

Similar Questions

Which of the following species is expected to show the highest magnetic moment? (At. Nos.: $Cr = 24$,$Mn = 25$,$Co = 27$,$Ni = 28$,$Cu = 29$)

Which of the following transition metal ion compounds has a magnetic moment of $4.90 \ BM$?

The correct order of the following $3d$ metal oxides,according to their oxidation numbers is:
$(a)$ $CrO_3$ $(b)$ $Fe_2O_3$ $(c)$ $MnO_2$ $(d)$ $V_2O_5$ $(e)$ $Cu_2O$

Identify the order in which the spin-only magnetic moment (in $BM$) increases for the following four ions:
$(I) Fe^{2+}$
$(II) Ti^{2+}$
$(III) Cu^{2+}$
$(IV) V^{2+}$

Identify the incorrect statement among the following.

Vedclass Test Series

Exam Paper Generator

Online Exam Module