Which of the following is a normal element

Options

A. Ce
B. He
C. Li
D. Ar

Answer

To determine which of the given elements is a normal element, we need to understand what a "normal element" refers to in the context of chemistry. A normal element typically refers to elements that are commonly found in nature and are not classified as noble gases, alkali metals, or other specialized categories.

Let's analyze the given options step by step:

1. **Identify the Elements**: The elements provided are:
- Cm (Curium)
- He (Helium)
- Li (Lithium)
- Ar (Argon)

2. **Classify Each Element**:
- **Curium (Cm)**: This is a synthetic element and part of the actinide series. It is not considered a "normal" element as it is not commonly found in nature.
- **Helium (He)**: This is a noble gas. Noble gases are generally not classified as normal elements because they have very low reactivity.
- **Lithium (Li)**: This is an alkali metal. Alkali metals are also not considered normal elements due to their high reactivity.
- **Argon (Ar)**: Like helium, argon is a noble gas and is not classified as a normal element.

3. **Determine the Normal Element**:
- Among the options, none of the elements fit the traditional definition of a normal element. However, if we consider the context of the question, lithium (Li) is often referred to as a more typical element compared to the others, as it is a common metal found in nature and used in various applications.

4. **Conclusion**:
- Based on the classifications and common usage, the most appropriate answer to the question "Which of the following is a normal element?" is **Lithium (Li)**.

### Final Answer:
Lithium (Li) is considered the normal element among the given options.

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