The 'acid value' of an oil or fat is measured in terms of weight of

Options

A. `NH_4 OH`
B. NaOH
C. KOH
D. `CH_3COOH`

Explanation

To determine the acid value of an oil or fat, we need to understand what the acid value represents and how it is calculated. Here’s a step-by-step solution:

### Step 1: Define Acid Value
The acid value is a measure of the amount of free fatty acids present in a fat or oil. It indicates the extent of hydrolysis or rancidity of the fat.

### Step 2: Understand the Measurement
The acid value is defined as the number of milligrams of potassium hydroxide (KOH) required to neutralize 1 gram of the fat or oil sample.

### Step 3: Calculation of Acid Value
To calculate the acid value, you would typically perform a titration where you add a known concentration of KOH to the fat or oil sample until the solution reaches a neutral pH. The amount of KOH used in milligrams is then related to the weight of the fat or oil in grams.

### Step 4: Expressing the Acid Value
The acid value can be expressed mathematically as:
\[ \text{Acid Value} = \frac{\text{mg of KOH required}}{\text{weight of fat or oil (in grams)}} \]

### Step 5: Conclusion
Thus, the acid value of an oil or fat is measured in terms of the weight of KOH required to neutralize 1 gram of that oil or fat.

### Final Answer
The 'acid value' of an oil or fat is measured in terms of the weight of KOH (in milligrams) required to neutralize 1 gram of the oil or fat.

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