Atoms of eight elements A, B, D, E, F, G and H have the same number of electronic shells but different number of electrons in their outermost shell. It was found that elements A and G combine to form an ionic compound. This compound is added in a small amount to almost all vegetable dishes during cooking. Oxides of elements A and B are basic in nature while those of E and F are acidic. The oxide of D is almost neutral. Based on the above information answer the following questions: Which one of the eight elements is most likely to be found in gaseous state at room temperature?

Explanation

To determine which of the eight elements (A, B, D, E, F, G, and H) is most likely to be found in the gaseous state at room temperature, we can analyze the information provided in the question step by step.

### Step 1: Identify the nature of the elements
The question states that all eight elements have the same number of electronic shells but different numbers of electrons in their outermost shell. This means they belong to the same period in the periodic table. Elements in the same period can be metals, non-metals, or metalloids.

### Step 2: Analyze the properties of the elements
- Elements A and G combine to form an ionic compound, which suggests that A is a metal and G is a non-metal (likely a halogen).
- The oxides of elements A and B are basic, indicating that A and B are likely metals.
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