3. Atoms change into other atoms in chemical reactions.
The idea that you can transform one element into another was called alchemy, and was proven untrue a long time ago.
Muddy water is indeed a mixture
Ok so we know that all of these are non metals therefore they will bond using covalent bonds.
Phoshorus can have 3 bonds Chlorine can have 1 bond and Oxygen can two bonds.
Cl-P=O
The chemical formula I belive is PClO hope this helps :).