The following `pH` range where the indicator shows change in colour are given
i. `4 - 9.7` ii. `7.46-10.0` iii. `6.5-4`
Which of the above `pH` range represent titration of
I. Strong acid/strong base `(S_(A)//S_(B))`,
II. Weak acid/strong base `(W_(A)//S_(B))`,
III. Weak base/strong acid `(W_(B)//S_(A))`

Options

A. `(i) rarr I, (ii) rarr II, (iii) rarr III`
B. `(iii) rarr I, (ii) rarr II, (i) rarr III`
C. `(ii) rarr I, (iii) rarr II, (i) rarr III`
D. `(i) rarr I, (iii) rarr II, (ii) rarr III`

Answer

To solve the question regarding the pH ranges and their corresponding titration types, we can follow these steps:

### Step 1: Identify the pH range for Strong Acid/Strong Base (SA/SB) Titration
- **Explanation**: In a titration between a strong acid and a strong base, the resulting solution typically has a pH around 7 at the equivalence point. Therefore, the pH range for the indicator should include neutral pH (around 7).
- **Given Range**: The range provided is **4 - 9.7**. This range includes pH 7, making it suitable for SA/SB titration.

### Step 2: Identify the pH range for Weak Acid/Strong Base (WA/SB) Titration
- **Explanation**: In a titration of a weak acid with a strong base, the pH at the equivalence point will be greater than 7 due to the basic nature of the strong base dominating the weak acid. Thus, the pH range should be above 7.
- **Given Range**: The range provided is **7.46 - 10.0**. This range is above pH 7, making it suitable for WA/SB titration.

### Step 3: Identify the pH range for Weak Base/Strong Acid (WB/SA) Titration
- **Explanation**: In a titration of a weak base with a strong acid, the pH at the equivalence point will be less than 7 because the strong acid will dominate. Therefore, the pH range should be below 7.
- **Given Range**: The range provided is **6.5 - 4**. This range is below pH 7, making it suitable for WB/SA titration.

### Summary of Results
- **i. 4 - 9.7**: Strong Acid/Strong Base (SA/SB)
- **ii. 7.46 - 10.0**: Weak Acid/Strong Base (WA/SB)
- **iii. 6.5 - 4**: Weak Base/Strong Acid (WB/SA)

### Final Answer
- i. Strong Acid/Strong Base: **4 - 9.7**
- ii. Weak Acid/Strong Base: **7.46 - 10.0**
- iii. Weak Base/Strong Acid: **6.5 - 4**