Question

Milk is an emulsion of water in oil type.
A.True
B.False
C.Ambiguous
D.Data insufficient

Answer 1

Hint: To answer this question recall the definition of emulsion. An emulsion consists of a fine dispersion of minute droplets where one liquid is not soluble or miscible in another liquid. This results in formation of a dispersed phase and dispersion medium.

Complete Step by step answer:
We know from the definition of emulsions that the combination of two liquids that normally don't mix result in a partial dispersed phase. There are two types of emulsions:
1.Oil in water (o/w) type: In these emulsions, oil forms the dispersed phase and water in the dispersion medium. For example, milk, vanishing cream, etc. These are also called aqueous emulsions.
2.Water in oil (w/o) type: In these emulsions, water is in the dispersed phase and oil in the dispersion medium. For example, butter, cold cream etc. These are also called oil emulsions.
 From the above explanations, we observe that milk is an oil in water emulsion It contains small bubbles of fat molecules dispersed in the solvent. Thus, the given statement is false.

Additional information:
Emulsions can be formed by mechanical means, such as agitation, provided that the liquids that are mixed have no mutual solubility. Mechanical stability is imparted by agents that form films at the surface of the droplets e.g., soap molecules, colloidal carbon or bentonite. Stable emulsions can be destroyed by inactivating or destroying the protective agent.

Note: A student can confuse Oil in water (o/w) type and Water in oil (w/o) type. Make sure you remember that in oil in water (O/W) emulsion, the oil will be the dispersed phase and water will be the dispersion medium while in water in oil (w/o) type, water will be the dispersed phase and oil will be the dispersion medium