Question

Which of the following everyday activities are physical changes, and which are chemical changes?

a)salting ice on a driveway
b)burning leaves
c)mixing sand with soil
d)composting cut vegetation
e)using a glue gun

a = physical
b = chemical
c = ?
d = ?
e = chemical

Please correct me if I'm wrong, and I am not sure of c and d, which is why I have not provided an answer.

Answer 1

a is right. b is right. e is wrong.
c. mixing sand with soil. What different substance was formed? None, therefore, this a physical change. Same as adding water to a glass from the faucet.

d.This can be viewed two ways. If you are talking about the composting itself (that is, the act of composting) it is a physical change. That is no different than placing the morning newspaper in a chair or throwing it in the garbage bag. But if you are talking about what happens to the compost pile AFTER all of it has been mixed up, that is a decaying reaction and that is chemical.
e.Using a glue gun means pulling the trigger of the gun. That is a physical change. Same thing as opening the faucet to pour a glass of water.

Answer 2

Thanks for your great explanation, I am able to understand better, thank you:-)