Consider the `M(OH)_(3)` formed by all the group 13 elements. The correct sequence of acidic strength of hydroxides `[M(OH)_(3)]` is-

Options

A. `B(OH)_3gt Al(OH)_3gt Ga(OH)_3gt In(OH)_3 gt TI(OH)_3`
B. `B(OH)_3lt Al(OH)_3gt Ga(OH)_3gt In(OH)_3 gt Tl(OH)_3`
C. `B(OH)_3gtTl(OH)_3gt Al(OH)_3gt In(OH)_3 gt Ga(OH)_3 `
D. `Al(OH)_3gtGa(OH)_3gtB(OH)_3gtIn(OH)_3gtTl(OH)_3`

Answer

To determine the correct sequence of acidic strength of the hydroxides \( M(OH)_3 \) formed by the group 13 elements (Boron, Aluminium, Gallium, Indium, and Thallium), we can follow these steps:

### Step 1: Identify the Group 13 Elements
The group 13 elements are:
- Boron (B)
- Aluminium (Al)
- Gallium (Ga)
- Indium (In)
- Thallium (Tl)

### Step 2: Understand the Concept of Acidic Strength
The acidic strength of a hydroxide is influenced by the electronegativity of the central atom. Higher electronegativity generally leads to stronger acidic behavior in hydroxides.

### Step 3: Analyze the Trend of Electronegativity in Group 13
As we move down the group from Boron to Thallium:
- The atomic size increases due to the addition of electron shells.
- The effective nuclear charge experienced by the outermost electrons decreases.
- Consequently, electronegativity decreases.

### Step 4: Relate Electronegativity to Acidic Strength
Since acidic strength is directly proportional to electronegativity:
- Boron, being the highest in electronegativity, will have the strongest acidic hydroxide.
- As we move down to Aluminium, Gallium, Indium, and Thallium, the acidic strength will decrease.

### Step 5: Establish the Sequence of Acidic Strength
Based on the above analysis, the sequence of acidic strength of the hydroxides \( M(OH)_3 \) is:
1. \( B(OH)_3 \) (strongest)
2. \( Al(OH)_3 \)
3. \( Ga(OH)_3 \)
4. \( In(OH)_3 \)
5. \( Tl(OH)_3 \) (weakest)

### Final Answer
The correct sequence of acidic strength of hydroxides \( M(OH)_3 \) is:
\[ B(OH)_3 > Al(OH)_3 > Ga(OH)_3 > In(OH)_3 > Tl(OH)_3 \]