The common transition metals in brass and bronze is

Options

A. Cu
B. Al
C. Sn
D. Cr

Answer

To solve the question regarding the common transition metals in brass and bronze, we will follow these steps:

### Step 1: Identify the Composition of Brass and Bronze
- **Brass** is an alloy primarily composed of **copper (Cu)** and **zinc (Zn)**.
- **Bronze** is an alloy primarily composed of **copper (Cu)** and **tin (Sn)**.

### Step 2: Determine the Common Metal
- From the compositions identified, both brass and bronze contain **copper (Cu)**. Therefore, copper is the common metal in both alloys.

### Step 3: Verify if Copper is a Transition Metal
- Transition metals are defined as those metals that have partially or incompletely filled d-orbitals.
- The atomic number of copper is **29**. Its electronic configuration is:
- **Cu:** \( \text{[Ar]} 3d^{10} 4s^1 \)
- In its elemental form, copper has a completely filled d-orbital (10 electrons in the 3d subshell).

### Step 4: Consider the Oxidation State of Copper
- When copper is oxidized to **Cu²⁺**, its atomic number becomes **27**. The electronic configuration changes to:
- **Cu²⁺:** \( \text{[Ar]} 3d^9 \)
- In this oxidized state, copper has an incompletely filled d-orbital (9 electrons in the 3d subshell).

### Conclusion
- Since copper has an incompletely filled d-orbital in its oxidized state, it qualifies as a transition metal.
- Therefore, the common transition metal present in both brass and bronze is **copper (Cu)**.

### Final Answer
The common transition metal in brass and bronze is **Cu (copper)**.

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