Which group elements of first transition series has the highest paramagnetism in elemental form of +1 O.S, +2 O.S. and +3 O.S.(O.S.= Oxidation state) respectively ?

Options

A. Group 6, Group 7, Group 7, Group 8
B. Group7, Group 6, Group 5, Group 8
C. Group 8, Group 9, Group10, Group 11
D. Group 3, Group 4, Group 5, Group 6

Answer

To solve the problem of determining which group elements of the first transition series have the highest paramagnetism in elemental form and in oxidation states of +1, +2, and +3, we will follow these steps:

### Step 1: Understanding Paramagnetism
Paramagnetism arises from the presence of unpaired electrons in an atom or ion. The more unpaired electrons there are, the higher the paramagnetism. The magnetic moment (μ) can be calculated using the formula:
\[ \mu = \sqrt{n(n + 2)} \]
where \( n \) is the number of unpaired electrons.

### Step 2: Identify the Elemental State
For the elemental state, we need to find the element in the first transition series (3d series) with the highest number of unpaired electrons.
- **Chromium (Cr)** has an atomic number of 24 and an electronic configuration of \( [Ar] 3d^5 4s^1 \).
- This gives it 6 unpaired electrons (5 from \( 3d \) and 1 from \( 4s \)).

**Conclusion for Elemental State:**
- **Element:** Chromium (Cr)
- **Group:** 6
- **Unpaired Electrons:** 6

### Step 3: Determine the +1 Oxidation State
For the +1 oxidation state, we need to find which element has the highest number of unpaired electrons.
- **Manganese (Mn)** has an atomic number of 25 and an electronic configuration of \( [Ar] 3d^5 4s^2 \).
- In the +1 oxidation state, its configuration becomes \( 3d^5 4s^1 \), resulting in 6 unpaired electrons.

**Conclusion for +1 Oxidation State:**
- **Element:** Manganese (Mn)
- **Group:** 7
- **Unpaired Electrons:** 6

### Step 4: Determine the +2 Oxidation State
For the +2 oxidation state, we again look for the element with the highest number of unpaired electrons.
- **Manganese (Mn)** in the +2 oxidation state has the configuration \( 3d^5 4s^0 \), resulting in 5 unpaired electrons.

**Conclusion for +2 Oxidation State:**
- **Element:** Manganese (Mn)
- **Group:** 7
- **Unpaired Electrons:** 5

### Step 5: Determine the +3 Oxidation State
For the +3 oxidation state, we need to find the element with the highest number of unpaired electrons.
- **Iron (Fe)** has an atomic number of 26 and an electronic configuration of \( [Ar] 3d^6 4s^2 \).
- In the +3 oxidation state, its configuration becomes \( 3d^5 4s^0 \), resulting in 5 unpaired electrons.

**Conclusion for +3 Oxidation State:**
- **Element:** Iron (Fe)
- **Group:** 8
- **Unpaired Electrons:** 5

### Final Summary
- **Elemental State:** Chromium (Group 6)
- **+1 Oxidation State:** Manganese (Group 7)
- **+2 Oxidation State:** Manganese (Group 7)
- **+3 Oxidation State:** Iron (Group 8)

### Final Answer
The group elements of the first transition series with the highest paramagnetism in elemental form, +1 O.S., +2 O.S., and +3 O.S. are:
- **Elemental State:** Group 6 (Chromium)
- **+1 O.S.:** Group 7 (Manganese)
- **+2 O.S.:** Group 7 (Manganese)
- **+3 O.S.:** Group 8 (Iron)

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