Which pair has both members from the same period of periodic table?

Options

A. Cl.Br
B. Ca,Cl
C. Na,Ca
D. Na,Cl

Answer

To solve the question "Which pair has both members from the same period of the periodic table?", we can follow these steps:

### Step 1: Understand the Structure of the Periodic Table
The periodic table is organized into horizontal rows called periods and vertical columns called groups. Each period represents a different energy level of electrons.

### Step 2: Identify the Periods
There are 7 periods in the periodic table. Elements in the same period have the same highest energy level of electrons.

### Step 3: Analyze the Given Pairs
We need to analyze the pairs mentioned in the video transcript:

1. **Chlorine (Cl) and Bromine (Br)**:
- Chlorine is in Period 3.
- Bromine is in Period 4.
- **Conclusion**: They are not in the same period.

2. **Sodium (Na) and Calcium (Ca)**:
- Sodium is in Period 3.
- Calcium is in Period 4.
- **Conclusion**: They are not in the same period.

### Step 4: Find a Suitable Pair
To answer the question, we need to find a pair of elements that are in the same period. For example:
- **Lithium (Li) and Beryllium (Be)**:
- Lithium is in Period 2.
- Beryllium is also in Period 2.
- **Conclusion**: They are in the same period.

### Final Answer
A suitable pair that belongs to the same period is **Lithium (Li) and Beryllium (Be)**.

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