Total number of elements present in 5 th period of modern periodic table is

Options

A. 2
B. 8
C. 18
D. 32

Answer

To determine the total number of elements present in the 5th period of the modern periodic table, we can follow these steps:

### Step 1: Understand the Structure of the Periodic Table
The periodic table is organized into periods (horizontal rows) and groups (vertical columns). Each period corresponds to the filling of electron shells.

### Step 2: Identify the Elements in the 5th Period
The 5th period consists of:
- **s-block elements**: 2 elements (from Group 1 and Group 2)
- **p-block elements**: 6 elements (from Groups 13 to 18)
- **d-block elements**: 10 elements (transition metals)

### Step 3: Count the Elements
Now, let's count the total number of elements in the 5th period:
- s-block: 2 elements
- d-block: 10 elements
- p-block: 6 elements

Total = 2 (s-block) + 10 (d-block) + 6 (p-block) = 18 elements

### Step 4: Conclusion
Thus, the total number of elements present in the 5th period of the modern periodic table is **18**.

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