The most abundant transition metal in earth crust is :

Options

A. Iron
B. Copper
C. Aluminium
D. Zinc

Answer

To determine the most abundant transition metal in the Earth's crust from the options provided (Iron, Copper, Aluminium, and Zinc), we can follow these steps:

### Step 1: Understand the Definition of Transition Metals
Transition metals are defined as metals that have partially filled d-orbitals in both their ground state and in at least one of their oxidation states.

### Step 2: Analyze the Given Options
We need to examine the abundance of each metal in the Earth's crust and check if they qualify as transition metals.

1. **Aluminium (Al)**:
- Abundance: Approximately 8.23% in the Earth's crust.
- Electronic Configuration: Ne (1s² 2s² 2p⁶) 3s² 3p¹.
- Conclusion: Aluminium does not have d-orbitals, so it is not a transition metal.

2. **Iron (Fe)**:
- Abundance: Approximately 5.63% in the Earth's crust.
- Electronic Configuration: Ar (1s² 2s² 2p⁶ 3s² 3p⁶) 3d⁶ 4s².
- Conclusion: Iron has partially filled d-orbitals, making it a transition metal.

3. **Zinc (Zn)**:
- Abundance: Approximately 0.007% in the Earth's crust.
- Electronic Configuration: Ar (1s² 2s² 2p⁶ 3s² 3p⁶) 3d¹⁰ 4s².
- Conclusion: Zinc has completely filled d-orbitals, so it is not considered a transition metal.

4. **Copper (Cu)**:
- Abundance: Approximately 0.006% in the Earth's crust.
- Electronic Configuration: Ar (1s² 2s² 2p⁶ 3s² 3p⁶) 3d¹⁰ 4s¹.
- Conclusion: Copper has a filled d-orbital in its ground state, but in its oxidation state (Cu²⁺), it has partially filled d-orbitals. However, its abundance is very low.

### Step 3: Compare the Abundances
Now we compare the abundances of the transition metals identified:
- Iron: 5.63%
- Copper: 0.006%
- Zinc: 0.007%
- Aluminium: Not a transition metal

### Step 4: Conclusion
Among the transition metals analyzed, Iron is the most abundant transition metal in the Earth's crust.

### Final Answer
The most abundant transition metal in the Earth's crust is **Iron**.

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