Hydrogen is usually –1. This is INCORRECT. The oxidation number for H is +1.
Oxygen is usually –2. This is CORRECT.
A pure group 1 element is +1. This is INCORRECT. It does not follow. This will depend on the other elements and the overall charge.
A monatomic ion is 0. This is INCORRECT. Diatomic ion is 0.
2,8,3 because Aluminium has the Atomic Number 13
Solid - made up of tightly packed particles, which gives it a solid shape.
Gas - made up of very loose particles, giving it more freedom to roam around as a gas
Liquid - fills into whatever it gets put in, basically takes the shape of the object its in
It turns liquid to gas. Hoped this helped!!