Element A of group VA combines with element B of group VI A. The resulting compound may have the formula?

Options

A. `A_2 B_3 `
B. `A_3 B_2 `
C. `A_5 B_6 `
D. `A_6 B_5 `

Answer

To solve the problem of determining the formula of the compound formed between element A from group VA and element B from group VIA, we can follow these steps:

### Step 1: Identify the Groups
- **Element A** is from group VA (5A), which corresponds to the nitrogen family. Common elements in this group include nitrogen (N), phosphorus (P), arsenic (As), etc.
- **Element B** is from group VIA (6A), which corresponds to the oxygen family. Common elements in this group include oxygen (O), sulfur (S), selenium (Se), etc.

### Step 2: Determine the Valency
- Elements in group VA typically have a valency of **3**. This is because they need to gain 3 electrons to achieve a stable octet configuration (like noble gases).
- Elements in group VIA typically have a valency of **2**. This is because they need to gain 2 electrons to achieve a stable octet configuration.

### Step 3: Combine the Valencies
To find the formula of the compound formed by these two elements, we need to balance their valencies:
- The valency of element A (from group VA) is **3**.
- The valency of element B (from group VIA) is **2**.

To balance these, we can use the concept of the least common multiple (LCM):
- The LCM of 3 and 2 is **6**.
- Therefore, we need **2** atoms of element A (valency 3) and **3** atoms of element B (valency 2) to balance the charges.

### Step 4: Write the Formula
- The resulting formula for the compound will be **A2B3**. This indicates that for every 2 atoms of element A, there are 3 atoms of element B.

### Conclusion
The resulting compound formed by element A from group VA and element B from group VIA will have the formula **A2B3**.

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