As we move across a period from left to right, nonmetallic character________ (decreases/increases)

Explanation

To answer the question, "As we move across a period from left to right, nonmetallic character __________ (decreases/increases)," we will analyze the trends in the periodic table, particularly focusing on the changes in nonmetallic character as we move across a period.

### Step-by-Step Solution:

1. **Understanding Periods in the Periodic Table**:
- The periodic table is organized into periods (horizontal rows) and groups (vertical columns). Each period corresponds to a principal energy level of electrons.

2. **Atomic Number and Electron Configuration**:
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