The gold number of Galatin . Gum and Starch are 0.005, 0 . 15 and 25 respectively . Which colloid has highest protection power ?

Options

A. Gelatin
B. Starch
C. Gum
D. All have equal protection power

Answer

To determine which colloid has the highest protection power based on the provided gold numbers, follow these steps:

### Step 1: Understand the Concept of Gold Number
The gold number is defined as the amount of a lyophilic sol (such as gelatin, gum, or starch) required to prevent the coagulation of a lyophobic sol (like gold sol) when an electrolyte is added. A smaller gold number indicates a higher protection power.

### Step 2: Identify the Gold Numbers
From the question, we have the following gold numbers:
- Gelatin: 0.005
- Gum: 0.15
- Starch: 25

### Step 3: Compare the Gold Numbers
Now, we need to compare the gold numbers:
- Gelatin: 0.005 (smallest)
- Gum: 0.15
- Starch: 25 (largest)

### Step 4: Determine the Highest Protection Power
Since a smaller gold number indicates a higher protection power, we can conclude:
- Gelatin has the smallest gold number (0.005), which means it has the highest protection power among the three colloids.

### Conclusion
Therefore, the colloid with the highest protection power is **gelatin**.

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