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 two of these elements could definitely be metals?

Explanation

To determine which two of the elements A, B, D, E, F, G, and H could definitely be metals based on the information provided, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Elements and Their Properties**:
- We know that A and G combine to form an ionic compound, which is commonly salt (NaCl). This indicates that A is likely a metal (sodium, Na) and G is a non-metal (chlorine, Cl).
- The oxides of elements A and B are basic, while those of E and F are acidic, and the oxide of D is neutral.

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