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.
Answer:
I think the answer is 4) 41
Explanation:
APE= atomic number, proton and the electrons are the same number
MAN= mass = atomic number - neutrons
121 - 80 = 41
i haven't done this in a while so hope this helps :)
Mass of reactants > mass of products