Which of the following properties are related to the complex $[Fe(H_2O)_6]^{3+}$?

(A) Paramagnetic
(B) number of unpaired electrons are five
(C) $d^2sp^3$ hybridisation
(D) $H_2O$ is a strong field ligand

Choose the correct answer from the options given below:

(A) and (B) only

The correct answer is Option (2) → (A) and (B) only

In complexes, magnetic behavior depends on unpaired d-electrons.

$\text{H}_2\text{O}$ is a weak field ligand in the spectrochemical series.

$\text{Fe}^{3+} \rightarrow$ atomic number $26 \rightarrow \text{Fe}^{3+} = \mathbf{3d^5}$ configuration.

Metal Ion:

$Fe^{3+} \rightarrow \text{remove 3 electrons from } Fe \rightarrow \mathbf{3d^5}$

Ligand Strength:

$H_2O$ is a weak field ligand, so it forms a high-spin complex.

Electron Arrangement (Octahedral Field):

$t_{2g}^3 \, e_g^2 \rightarrow \mathbf{5 \text{ unpaired electrons}}$

Option-wise Explanation

(A) Paramagnetic

True. Presence of unpaired electrons causes paramagnetism. Here we have 5 unpaired electrons.

(B) Number of unpaired electrons are five

True. High-spin $d^5$ configuration gives one electron in each d orbital.

(C) $d^2sp^3$ Hybridisation

False. Weak field ligands cause outer orbital complex $\rightarrow \mathbf{sp^3d^2}$ hybridisation, not $d^2sp^3$.

(D) $H_2O$ is a strong field ligand

False. $H_2O$ lies in the middle of spectrochemical series and behaves as weak field.