Question

Find the oxidation number of Pt in H2(ptCl6)

Answer 1

it is 4+. because H+ has two molecules and Cl - has six, and the charge of the compound must be zero(0), so the charge of hydrogen (+1 * 2 = 2) plus charge of chloride (-1 * 6 = 6) and adding the Platinum charge must be positive four :
H+ * 2 = 2
Cl- *6 = -6
Pt+ * 4 = 4
total charge of compound= 0H2PtCl6?
6Cl-is 6 -
2H 2+
Pt is  4+,because is only one atom of it

Answer 2

sum of oxidation number of all atom of H2PtCl6=0

...here consider as oxidation number of Pt is x.

now ,

2(oxidation number of H)+(oxidation number of Pt)+6(oxidation number of Cl) = 0

2(+1)+x+6(-1)=0 ....( here oxidation number of H is +1 , oxidation number of Cl is -1)

x-4=0

x=+4

therefore ,

oxidation number of Pt in H2PtCl6 is +4.

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