General oxidation state shown by group 13 elements is

Options

A. `+1 and +3`
B. `+1,+2 and +3`
C. `+2,+3 and +4`
D. `+1 and +4`

Answer

To determine the general oxidation state shown by group 13 elements, we can follow these steps:

### Step 1: Identify Group 13 Elements
Group 13 elements include boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Tl).

### Step 2: Understand Oxidation States
The oxidation states of elements in a group can vary. For group 13 elements, the common oxidation states are +3 and +1.

### Step 3: Analyze the Oxidation States of the Elements
- **Boron (B)** and **Aluminum (Al)** typically exhibit a +3 oxidation state in their compounds, such as BCl3 and AlCl3.
- As we move down the group to **Indium (In)** and **Thallium (Tl)**, we notice a trend where the +1 oxidation state becomes more stable. For example, thallium can form TlCl and TlBr, where it shows a +1 oxidation state.

### Step 4: Consider the Inert Pair Effect
The inert pair effect refers to the tendency of the outermost s-electrons to remain non-bonding as we go down the group. This effect becomes more pronounced in heavier elements, leading to a preference for the +1 oxidation state over the +3 state.

### Step 5: Conclusion
Thus, the general oxidation states shown by group 13 elements are +1 and +3, with +1 being more stable for the heavier elements.

### Final Answer
The general oxidation states shown by group 13 elements are +1 and +3.

---