In a square close packing pattern, one atom is in contact with how many atom in the 2D plane base ?

Options

A. 2
B. 4
C. 6
D. 8

Explanation

To solve the question regarding how many atoms one atom is in contact with in a square close packing pattern in a 2D plane base, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Square Close Packing**:
- In a square close packing arrangement, atoms are arranged in a 2D plane such that they form a square grid. Each atom is positioned at the corners of squares.

2. **Visualizing the Arrangement**:
- Imagine a central atom placed in the middle of a square. This atom will have other atoms positioned around it.

3. **Identifying Neighboring Atoms**:
- In this arrangement, the central atom will be in contact with the atoms that are directly adjacent to it.
- Specifically, there will be one atom directly above, one directly below, one to the left, and one to the right of the central atom.

4. **Counting the Contacts**:
- Therefore, the central atom is in contact with a total of 4 surrounding atoms (one from each direction: up, down, left, and right).

5. **Conclusion**:
- Hence, in a square close packing pattern, one atom is in contact with **4 atoms** in the 2D plane base.

### Final Answer:
In a square close packing pattern, one atom is in contact with **4 atoms** in the 2D plane base.

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