Question

Match List I with List II

	List I-Buffers		List II-pH Value
A	HCl and KCl	I	8 to 10
B	HCl and Potassium Hydrogen Phthalate	II	2.2 to 4.0
C	NaOH and Potassium Hydrogen Phthalate	III	1.2 to 2.2
D	H3BO3, NaOH, and KCl	IV	4.2 to 5.8

Choose the correct answer from the options given below:

• A. A ‐II , B ‐III , C ‐IV , D ‐I
• B. A ‐III , B ‐II , C ‐IV , D ‐I
• C. A ‐II , B ‐IV , C ‐I , D ‐II
• D. A ‐III , B ‐IV , C ‐II , D ‐I

Answer 1

The Correct Option is B

To solve the question, we need to match the buffers in List I with their correct pH value ranges in List II. Let's analyze each pair:

1. Buffer A: HCl and KCl
   This is a buffer made from a strong acid (HCl) and its salt (KCl). Typically, such combinations maintain a very low pH, usually in the range of about 1.2 to 2.2. Thus, it matches with pH range III (1.2 to 2.2).
2. Buffer B: HCl and Potassium Hydrogen Phthalate (KHP)
   Potassium hydrogen phthalate (KHP) is used to create acidic buffer solutions. The pH range for this buffer setup is generally between 2.2 and 4.0. Thus, it matches with pH range II (2.2 to 4.0).
3. Buffer C: NaOH and Potassium Hydrogen Phthalate (KHP)
   This buffer involves a base (NaOH) and an acidic salt (KHP). It typically stabilizes at a slightly acidic to neutral pH level, around 4.2 to 5.8. Therefore, it matches with pH range IV (4.2 to 5.8).
4. Buffer D: H₃BO₃, NaOH, and KCl
   This is a classic borate buffer with KCl providing ionic strength. Such buffers generally maintain a pH in the basic range, typically around 8.0 to 10.0. Hence, it matches with pH range I (8 to 10).

Using the above analysis, the correct matches are:

• A - III
• B - II
• C - IV
• D - I

Consequently, the correct option is A ‐III , B ‐II , C ‐IV , D ‐I.