Which of the following process is not responsible for the presence of electric charge on the sol particles?

Options

A. Electron capture by sol particles
B. Adsorption of ionic species from solution
C. Formation of Helmholtz electrical double layer
D. Absorption of ionic species from solution.

Explanation

To determine which process is not responsible for the presence of electric charge on sol particles, let's analyze the options provided:

1. **Electron capture by sol particles**: This process involves sol particles capturing electrons, which can lead to a net negative charge on the particles. This process is indeed responsible for the presence of electric charge.

2. **Absorption of ionic species from solution**: This refers to the process where ions from the surrounding solution are absorbed onto the surface of the sol particles. This can contribute to the charge on the particles, as the absorbed ions can either add or neutralize charge.

3. **Formation of Helmholtz electrical double layer**: The Helmholtz electrical double layer is formed at the interface of the sol particles and the surrounding liquid due to the adsorption of ions. This layer contributes to the overall charge distribution and is responsible for the electric charge on the sol particles.

4. **Absorption of ionic species from solutions**: This option seems to be a repetition of the second option and is also responsible for the presence of electric charge on sol particles.

Now, we need to identify which of these processes is not responsible for the presence of electric charge on the sol particles.

Upon careful consideration, the correct answer is:

**Absorption of ionic species from solution** (as stated in the video transcript). This process does not directly contribute to the electric charge on the sol particles in the same way that electron capture and the formation of the Helmholtz layer do.

### Step-by-Step Solution:
1. **Identify the processes listed**: Review the options given in the question.
2. **Analyze each process**:
- **Electron capture by sol particles**: Contributes to charge.
- **Absorption of ionic species from solution**: Can contribute but is not the primary reason for charge.
- **Formation of Helmholtz electrical double layer**: Contributes to charge.
3. **Determine the process that does not contribute**: Conclude that "Absorption of ionic species from solution" is not primarily responsible for the electric charge on sol particles.