An element 'X' has an atomic number 11 while an element 'Y' has an atomic number 17. They are expected to form

Options

A. an ionic compound with formula XY
B. an ionic compound with formula `XY_(2)`
C. a covalent compound with formula `XY_(2)`
D. a covalent compound with formula `X^(2)Y`

Explanation

To solve the problem, let's break it down step by step:

### Step 1: Identify the Elements
- Element 'X' has an atomic number of 11.
- Element 'Y' has an atomic number of 17.

### Step 2: Determine the Electronic Configurations
- For element 'X' (atomic number 11):
- K shell can hold 2 electrons: 2 electrons
- L shell can hold 8 electrons: 8 electrons
- M shell will hold the remaining electrons: 1 electron
- Thus, the electronic configuration of X is \(1s^2 2s^2 2p^6 3s^1\).

- For element 'Y' (atomic number 17):
- K shell: 2 electrons
- L shell: 8 electrons
- M shell: 7 electrons
- Thus, the electronic configuration of Y is \(1s^2 2s^2 2p^6 3s^2 3p^5\).

### Step 3: Analyze the Valence Electrons
- Element 'X' has 1 valence electron (in the 3s orbital).
- Element 'Y' has 7 valence electrons (2 in 3s and 5 in 3p).

### Step 4: Determine Stability and Electron Transfer
- Element 'X' can achieve stability by losing its 1 valence electron, resulting in a stable configuration of 8 electrons in the L shell.
- Element 'Y' can achieve stability by gaining 1 electron to complete its valence shell, reaching a stable configuration of 8 electrons.

### Step 5: Form the Compound
- When 'X' loses 1 electron, it becomes a positively charged ion (cation).
- When 'Y' gains 1 electron, it becomes a negatively charged ion (anion).
- The resulting ions will combine to form an ionic compound.

### Step 6: Write the Molecular Formula
- The molecular formula for the compound formed by 'X' and 'Y' will be XY, where:
- 'X' has a valency of +1 (as it loses 1 electron).
- 'Y' has a valency of -1 (as it gains 1 electron).

### Step 7: Identify the Type of Bond
- Since 'X' is electropositive (loses electrons) and 'Y' is electronegative (gains electrons), the bond formed between them is an ionic bond.

### Final Answer
- The elements 'X' and 'Y' are expected to form an ionic compound with the molecular formula XY.

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