Name or state the following with reference to the element of the first three periods of the periodic table.
Group whose elements have zero valency.

Explanation

To answer the question regarding the group of elements with zero valency in the first three periods of the periodic table, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Valency**: Valency refers to the ability of an element to combine with other elements, which is determined by the number of electrons in its outermost shell (valence shell). An element with zero valency does not need to gain or lose electrons to achieve a stable electronic configuration.

2. **Identify the Groups in the Periodic Table**: The periodic table is organized into groups (columns) and periods (rows). The first three periods consist of elements from Group 1 to Group 18.

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