Which of the following ions is paramagnetic?

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

Question

(B) To determine if an ion is paramagnetic,we check for the presence of unpaired electrons in its electronic configuration.$1$. $O_2^{2-}$ (Peroxide i

Vedclass · Accepted Answer

$Cr^{3+}$

Vedclass · Answer

(B) To determine if an ion is paramagnetic,we check for the presence of unpaired electrons in its electronic configuration.$1$. $O_2^{2-}$ (Peroxide ion): Total electrons = $8 + 8 + 2 = 18$. Configuration: $(\sigma 1s)^2, (\sigma^* 1s)^2, (\sigma 2s)^2, (\sigma^* 2s)^2, (\sigma 2p_z)^2, (\pi 2p_x)^2 = (\pi 2p_y)^2, (\pi^* 2p_x)^2 = (\pi^* 2p_y)^2$. All electrons are paired,so it is diamagnetic.$2$. $Cr^{3+}$: Atomic number of $Cr$ is $24$. Configuration of $Cr$ is $[Ar] 3d^5 4s^1$. $Cr^{3+}$ loses $3$ electrons: $[Ar] 3d^3$. It has $3$ unpaired electrons,so it is paramagnetic.$3$. $Na^+$: Atomic number $11$. Configuration: $1s^2 2s^2 2p^6$. All electrons are paired,so it is diamagnetic.$4$. $Cu^+$: Atomic number $29$. Configuration of $Cu$ is $[Ar] 3d^{10} 4s^1$. $Cu^+$ loses $1$ electron: $[Ar] 3d^{10}$. All electrons are paired,so it is diamagnetic.Therefore,$Cr^{3+}$ is the paramagnetic ion.

Aspects	Metal
$a$. The metal which reveals a maximum number of oxidation states	$i$. Scandium
$b$. The metal although placed in $3d$ block is considered not as a transition element	$ii$. Copper
$c$. The metal which does not exhibit variable oxidation states	$iii$. Manganese
$d$. The metal which in $+1$ oxidation state in aqueous solution undergoes disproportionation	$iv$. Zinc

List-$I$ ($\text{Transition metal ion}$)	List-$II$ ($\text{Spin only magnetic moment (B.M.)}$)
$A$. $Ti^{3+}$	$I$. $3.87$
$B$. $V^{2+}$	$II$. $0.00$
$C$. $Ni^{2+}$	$III$. $1.73$
$D$. $Sc^{3+}$	$IV$. $2.84$

Similar Questions

Name the periodic element,which does not show variable oxidation states.

Which of the following statements is $NOT$ true for transition metal elements?

Which of the following is a correct statement?

Match List-$I$ with List-$II$:
List-$I$ ($\text{Transition metal ion}$) List-$II$ ($\text{Spin only magnetic moment (B.M.)}$)
$A$. $Ti^{3+}$ $I$. $3.87$
$B$. $V^{2+}$ $II$. $0.00$
$C$. $Ni^{2+}$ $III$. $1.73$
$D$. $Sc^{3+}$ $IV$. $2.84$

Choose the correct answer from the options given below:

Vedclass Test Series

Exam Paper Generator

Online Exam Module