Identify the three elements `A, B and C` from the data given below
a. The elements have successive atomic numbers
b. `A` forms a stable anion, `A^(ɵ)`
c. `C` forms a stable cation, `C^(o+)`

Explanation

To solve the problem of identifying the three elements A, B, and C based on the given clues, we can follow these steps:

### Step 1: Understand the Clue about Successive Atomic Numbers
The first clue states that the elements A, B, and C have successive atomic numbers. This means if A has an atomic number Z, then B will have Z+1, and C will have Z+2.

### Step 2: Analyze the Clue about A Forming a Stable Anion
The second clue indicates that element A forms a stable anion (A⁻). Elements that typically form stable anions are found in the halogen group of the periodic table, which includes elements like fluorine (F), chlorine (Cl), bromine (Br), etc. These elements have seven valence electrons and can gain one electron to achieve a stable electron configuration.

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