Finding Charge

[Victoria Luu - 1C]

How exactly do you find the charge of a reactant if the charge is not given?

[Alexa Tabakian 1A]

Use the charges from the periodic table! Hope this helps!

[A De Castro 14B 2H]

If by "charge is not given," you mean that the molecule has a neutral charge, then the charge would be 0. For example, H₂O is a neutral molecule; it has a net charge of 0. Based on the charges from the periodic table, oxygen usually has a 2- charge while hydrogen usually has a + charge.
2H⁺ + O^2- → H₂O, so (2 x +1) + -2 = 0.

[Albert_Luu3K]

Usually if the charge is not given, that means the molecule is a neutral charge (0). Using that knowledge, you should be able to use the periodic table to find the oxidation state of one of the elements and deduct the oxidation state of the other.