Question

Churning of milk cream to get butter is a _ _ _ _ _ _ _ _ change.

Answer 1

Hint: Milk or milk cream is some-what liquid while the butter is solid. The churning of milk cream to get butter is the same type of change which is present when iron nails are mixed with wooden blocks or when sugar crystals are mixed with sand or wheat grains.

Complete answer:
We will first know about churning.
The Churning is the process of shaking up. The churning of milk is shaking up of milk to make butter. Scientifically, it is termed as centrifugation. This process is a physical process.
The Butter is actually the fat portion present in milk. During centrifugation, the heavy fat particles centrifugate at a place and we name it butter or butter churn.
So, there is not any chemical reaction that has occurred.
Thus, it is a physical change.

Additional information:
Butter is a semi-solid emulsion at room temperature and a solid at low temperature. It is melted as condiment and used as an ingredient in baking, sauce making and many other cooking techniques.

Note:
It must be noted that the chemical change involves any reaction to take place. The identity of the molecules get changed in the chemical change but in physical change, the identity of the molecules remain the same. In above also, the fat globules have clustered at one point. No change in identity of any molecule is observed.