Created By : Rina Nayak

Reviewed By : Rajashekhar Valipishetty

Last Updated : Apr 24, 2023

With the help of a buffer capacity calculator, we can calculate the buffer capacity in a liter of given solution. To get buffer capacity as output, we need to give inputs i.e amount of acid or base, initial pH value and final pH value in the input, then click the calculate button to avail the output.

Amount of acid/base
Initial pH
Final pH
Buffer capacity

### Buffer Capacity - Definition

Buffer Capacity can be defined as a quantity in resisting the pH change at the time of addition of an acid or base. The buffer capacity and initial pH affects the pH change on addition of acid base. More concentrated buffers will have higher capacity as they have more molecules to interact with additional bases or acids. Thus, a higher concentration buffer has a slower changer in pH.

### Buffer Capacity- Formula

In order to determine the buffer capacity you need to divide numbers of moles of acid /base you have added per liter of solution by change in the pH. Formula to find Buffer Capacity is given as 𝛃 = n/ 𝚫pH

• Where, Where 𝛃 is buffer capacity.
• n is the number of moles of acid / base added per liter of buffer solution
• 𝚫pH is the change in pH

By using Henderson - Hasselbalch equation we can calculate the pH value, pH = pKa + log10([A-]/[HA])

• [A-] is the concentration of a base in a buffer.
• [HA] is the concentration of an acid in a buffer.
• pKa is the dissociation constant of an acid

### How to calculate Buffer Capacity?

Step by step procedure to calculate the buffer capacity of a solution in a liter by using a buffer capacity calculator is given as follows

• Step 1: Know the value of n, mean number of moles of acid / base added per liter of buffer solution, enter the value.
• Step 2: Know the values of initial pH and final pH of the acids, get the change in pH by subtracting final pH from the initial pH.
• Step 3: Otherwise use Henderson - Hasselbalch Equation to get the pH
• Step 4: Enter the values of n and pH, then click the calculate button.

### Buffer Capacity Problems

Question 1: A buffer solution has an amount of acid with 0.02mol,initial pH and final pH is 4.75 and 5.20 , find buffer capacity (𝛃)?

Solution:

Given that,

n of moles of acid solution = 0.02mol

initial pH = 4.75

final pH = 5.20

Formula for buffer capacity 𝛃 = n/ 𝚫pH

Where 𝛃 is buffer capacity

n is the number of moles of acid / base added per liter of buffer solution

𝚫pH is the change in pH

𝚫pH = final pH -initial pH

= 5.20 - 4.75 = 0.45

𝛃 = n/ 𝚫pH 0.02 / 0.45 = 0.044mol

The buffer capacity of a solution is 0.044mol.

Question 2: Calculate the buffer capacity (𝛃) if you add 0.80 mol of HCL to 100ml to phosphate buffer and the pH drops exactly 1 unit?

Solution:

Given that,

n of moles of phosphate buffer is = 0.80 mol

𝚫pH is = 1

Formula for buffer capacity

𝛃 = n/ 𝚫pH

Where 𝛃 is buffer capacity

n is the number of moles of acid / base added per liter of buffer solution

is the change in pH

𝛃 = 0.80 / 1

= 0.80 moles

Therefore the buffer capacity is 0.80 mol

### FAQ’s on Buffer Capacity Calculator

1. What is meant by buffer capacity?

The amount of an acid or base that can be added to a volume of a buffer solution before its pH changes significantly.

2. What are the types of buffer solutions?

There are two types of buffer solutions , acidic buffers and another one is alka;ine buffers

3. Why is buffer capacity important?

Buffer capacity is a quantitative measure of resistance to pH change upon the addition of H+ and OH- ions. It is important for river water to maintain constant pH.

4. What is the good buffer capacity value ?

Buffer capacity ranges from 0.01 to 0.1, so it is a good buffer capacity used in several pharmaceutical solutions.

5. What is the formula of buffer capacity?

To find the buffer capacity , you need to divide the numbers of moles of acid /base you have added per liter of solution by change in the pH. 𝛃 = n/ 𝚫 pH

• Where 𝛃 is buffer capacity
• n is numbers of moles of acid / base
• 𝚫pH is the change in pH

6. What are blood buffers?

A chemical present in the blood that prevents rapid changes in pH.the principal buffers are carbonic acid,carbonates and bicarbonates,monobasic and dibasic phosphates and proteins such as hemoglobin.