Emulsions

Step 1: Understanding the emulsion formulation.
Turpentine oil emulsion typically requires a balanced mixture of oil, water, and gum to ensure a stable emulsion. The common formulation is in the ratio of 3 parts oil to 2 parts water and 1 part gum.
Step 2: Analyzing the options.
(1) 4:2:1: This is an incorrect formulation as it does not provide the ideal ratio for a turpentine oil emulsion.
(2) 3:2:1: Correct — This ratio is widely used to prepare the primary emulsion of turpentine oil.
(3) 2:2:1: This ratio is not ideal for stable emulsion formulation.
(4) 1:2:1: This ratio would not result in a proper emulsion of turpentine oil.
Step 3: Conclusion.
The correct formulation ratio is (2) 3:2:1, which is commonly used for the preparation of turpentine oil emulsion.