Silkworms feed on mulberry leaves and produce silk. Is this a chemical or physical change?

Answer 1

You can mainly distinguish one from antoher knowing that in physical changes the material stays the same, but changes one of its physical properties, while in chemistry we get totally new substances. The leaves are chemically sort of digested and the outcome using energy and different materials already present in the worms body make it be a mixture of other substances, so its chemical reaction. Most of issues occurring in a body is biochemical.

Answer 2

Mulberry leaves are digested and the worm produce pooh. That is a physical change - there is a direct link between the mouth and the anus - stuff in is changed to stuff out. The worm does not produce silk because it eats a lot. If that was the case, the worm would eat for a day or two and then produce silk and then eat again etc.

The energy (biochemically produced) are stored in the worm which become a pupae. Some of that energy is used to produce the silk through a silk gland - so it is a chemical reaction.

The food the worm eat have an influence on the colour of silk it produce. Mulberry leaves = yellow silk. Lettuce = White silk. Beetroot leaves = Red silk. This is also proof of the chemical reaction producing the silk.

Answer 3

Chemical - yes, certainly. A silk thread consists of different molecules than a mulbery leave.
Physical - maybe, depending on your definition. The atoms and subatomar particles don't change. The form, structure, density etc. do change.

Answer 4

It is a chemical change we can say

Answer 5

This is a physical change. No doubt.