Classify each of the following as a physical change or a chemical change. melting ice: souring of milk: digesting food: evaporating water?

- melting ice is a physical change

- souring of milk is a chemical change

- digesting food is a chemical change

- evaporating water is a physical change

Explanation:

A chemical change involves formation of new product and is irreversible, while physical change may involve the formation of new products and is easily reversible.

Physical Changes are described below

- Ice on melting forms water, that can be refrigerated to yield ice again

- water on evaporation during heating yields steam that can be condensed to yield water again.

Chemical change

- souring of milk involves bacteria oxidation of chemicals in the milk that changes its composition, smell, and taste; fresh milk CANNOT be obtained again

- food digestion involves mechanical breaking by teeth, stomach walls and several enzyme actions to yield glucose, amino acids etc. It cannot be reversed to whole food again

i'm pretty sure its b i might be wrong though!

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