Which of the following has minimum protecting power ?

Options

A. Gelatin (Gold no . = 0 . 0 1)
B. Dextrin (Gold no = 15)
C. Potato starch (Gold no . = 25)
D. Albumin (Gold no . = 0 . 25)

Answer

To determine which of the given options has the minimum protecting power, we need to understand the concept of the Gold number. The Gold number is defined as the minimum amount of a lyophilic colloid (in milligrams) required to prevent the coagulation of a given volume of a lyophobic colloid (like gold sol) when a specific amount of an electrolyte (like NaCl) is added.

### Step-by-Step Solution:

1. **Understand the Concept of Gold Number**:
- The Gold number indicates the protective power of a colloid. A lower Gold number means that less lyophilic colloid is required to prevent coagulation, indicating higher protecting power.

2. **Identify the Given Options**:
- The question likely provides a list of colloids with their respective Gold numbers. For example, options could include gelatin, gum arabic, and others.

3. **Compare the Gold Numbers**:
- Look at the Gold numbers of each colloid provided in the options. For example:
- Gelatin: Gold number = 0.1
- Gum Arabic: Gold number = 0.5
- Starch: Gold number = 1.0
- The colloid with the lowest Gold number has the highest protecting power.

4. **Determine the Minimum Protecting Power**:
- From the comparison, identify which colloid has the highest Gold number. This colloid will have the minimum protecting power since it requires more of the lyophilic colloid to prevent coagulation.

5. **Conclude the Answer**:
- Based on the Gold numbers compared, state which colloid has the minimum protecting power.