Which of the following is not a characteristic property of iron?

Options

A. Malleability
B. Brittleness
C. Ductility
D. Sonorousness

Explanation

To determine which of the following is not a characteristic property of iron, we first need to understand the properties of iron and metals in general. Here’s a step-by-step breakdown of the characteristics of iron:

### Step 1: Identify the Properties of Iron
Iron is a metal with several characteristic properties, including:
- **Conductivity**: Iron is a good conductor of heat and electricity.
- **Luster**: Iron has a shiny appearance when polished.
- **Sonority**: Iron produces a deep sound when struck.
- **Malleability**: Iron can be hammered into thin sheets without breaking.
- **Ductility**: Iron can be drawn into thin wires without breaking.

### Step 2: Identify the Non-Characteristic Property
Among the properties listed, we need to identify which one does not apply to iron. The properties of metals generally include conductivity, luster, sonority, malleability, and ductility.

### Step 3: Analyze the Options
If we consider the properties of iron, the term "brittleness" is often associated with non-metallic materials or certain alloys. Iron, in its pure form, is not considered brittle; rather, it is malleable and ductile.

### Conclusion
Thus, the property that is not characteristic of iron is **brittleness**.

### Final Answer
**Brittleness is not a characteristic property of iron.**

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