[Co(NH₃)₅Br]²⁺
Ligands and charges on them,
5 × NH₃ = 5 × 0 = 0
1 × Br⁻¹ = 1 × -1 = -1
Charge on sphere = +2
So, putting values in equation,
Co + (0)₅ - 1 = +2
Co + 0 - 1 = +2
Co - 1 = +2
Co = +2 + 1
Co = +3
Result:
Oxidation state of Co in [Co(NH₃)₅Br]²⁺ is +3.
What they have in common is that they both have the same number of atoms. Hope this helps. :)
In No3-1 the oxidation number of oxygen is -5 so oxidation number of N would be +5
Molar mass HNO₃ = 63.0 g/mol
number of moles = 3.94 / 63.0 => 0.0625 moles
Volume = moles / molarity
V = 0.0625 / 1.50
V = 0.04166 L x 1000 = 41.66 mL
hope this helps!
What do you mean by unlock all of them? Please explain