Which of the following will show increase in weight when kept in magnetic field

Options

A. `TiO_(2)`
B. `Fe_(2)(SO_(4))_(3)`
C. `KMnO_(4)`
D. `ScCl_(3)`

Explanation

To determine which of the given compounds will show an increase in weight when kept in a magnetic field, we need to analyze the magnetic properties of each compound based on the oxidation states and electronic configurations of the elements involved.

### Step-by-Step Solution:

1. **Identify the Compounds:**
The compounds given are:
- TiO2 (Titanium Dioxide)
- Fe2(SO4)3 (Iron(III) Sulfate)
- KMnO4 (Potassium Permanganate)
- SeCl3 (Selenium Trichloride)

2. **Analyze Each Compound:**
- **TiO2:**
- Titanium (Ti) has an oxidation state of +4 in TiO2.
- Electronic configuration of Ti in +4 state: [Ar] 3d0 4s0 (no unpaired electrons).
- **Magnetic Property:** Diamagnetic (no unpaired electrons), will not show an increase in weight.

- **Fe2(SO4)3:**
- Iron (Fe) has an oxidation state of +3 in Fe2(SO4)3.
- Electronic configuration of Fe in +3 state: [Ar] 3d5 (five unpaired electrons).
- **Magnetic Property:** Paramagnetic (presence of unpaired electrons), will show an increase in weight in a magnetic field.

- **KMnO4:**
- Manganese (Mn) has an oxidation state of +7 in KMnO4.
- Electronic configuration of Mn in +7 state: [Ar] 3d0 4s0 (no unpaired electrons).
- **Magnetic Property:** Diamagnetic (no unpaired electrons), will not show an increase in weight.

- **SeCl3:**
- Selenium (Se) has an oxidation state of +3 in SeCl3.
- Electronic configuration of Se in +3 state: [Ar] 3d10 4s2 4p1 (one unpaired electron).
- **Magnetic Property:** Paramagnetic (presence of unpaired electrons), may show an increase in weight, but typically less than that of Fe2(SO4)3 due to fewer unpaired electrons.

3. **Conclusion:**
- Among the given options, **Fe2(SO4)3** (Iron(III) Sulfate) is the compound that will show an increase in weight when kept in a magnetic field due to its paramagnetic nature with five unpaired electrons.

### Final Answer:
The correct answer is **Fe2(SO4)3**.