Atomic mass of an element is 24 and it contains K neutrons ,valency of the element is

Options

A. 1
B. 2
C. 3
D. 4

Explanation

To solve the problem step by step, we will determine the valency of the element based on the given atomic mass and the number of neutrons.

### Step 1: Identify the Atomic Mass and Neutrons
The atomic mass of the element is given as 24, and it contains K neutrons.

### Step 2: Determine the Atomic Number
The atomic number (Z) can be calculated using the formula:
\[ \text{Atomic Mass} = \text{Number of Protons} + \text{Number of Neutrons} \]
Since the number of protons is equal to the atomic number (Z), we can express this as:
\[ 24 = Z + K \]
From this equation, we can find the atomic number once we know K.

### Step 3: Calculate the Atomic Number
Assuming K is known, we can rearrange the equation to find Z:
\[ Z = 24 - K \]

### Step 4: Determine the Electronic Configuration
The atomic number (Z) tells us how many electrons are present in a neutral atom. The electronic configuration can be determined based on the atomic number. For example, if Z = 12, the electronic configuration would be:
\[ 2, 8, 2 \]

### Step 5: Identify Valence Electrons
The valence electrons are the electrons in the outermost shell. In the example of Z = 12, the outermost shell has 2 electrons (as seen in the configuration 2, 8, 2).

### Step 6: Determine the Valency
The valency of an element is determined by the number of electrons in the outermost shell that can be lost, gained, or shared to achieve a full outer shell (usually 8 electrons for main group elements).
- If there are 2 valence electrons, the valency is 2.

### Conclusion
Thus, if the atomic mass is 24 and assuming K neutrons leads to an atomic number of 12, the valency of the element is 2.

### Final Answer
The valency of the element is **2** (Option B).

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