Which of these are chemical changes and which are physical?

Question

This is for chemistry, but I'm having a really hard time understanding the difference.

- Boil

- Burn

- Condense

- Corrode

- Crumple

- Ferment

- Melt

- Rust

- Crush

- Freeze

- Oxidize

- Tarnish

- Explode

- Grind

- Rot

- Vaporize

Which are chemical and which are phsyical changes, and can you please explain to me how I would tell on a test? Thanks <3

Answer 1

p for physical c for chemical

pcpcpcpcppcccpcp

its chemical if a reaction takes place, like rusting, burning etc

physical if just squashed, bashed, or change of state from liquid to gas, gas to liquid, liquid to solid etc.

Answer 2

physical changes are changes of state, chemical changes involve change in atomic matter. You have to look up tarnish for example and study to find what is going on (any reactions?)

Answer 3

-Boil-Physical.

-Burn-Chemical.-

-Condense-Physical.

-Corrode-Chemical.

-Crumple-Physical.

-Ferment-Chemical.

-Melt-Physical.

-Rust-Chemical.

-Crush-Physical.

-Freeze-Physical.

-Oxidise-Chemical.

-Tarnish-Chemical.

-Explode-Chemical. (Or Physical as in the explosive decompression of a high pressure container should it rupture).

-Grind-Physical (Could also be Chemical as tiny sparks may -combust in the air).

-Rot-Chemical.

-Vaporise-Physical.