Assign oxidation number to the underlined elements in each of the following species:

NaBH4


Let the oxidation number(O.N.) of B be ‘x’


We know that,


O.N. of Na = + 1


O.N. of H = -1


Therefore , we have,


1(+ 1) + 1(x) + 4(-1) = 0


1 + x-4 = 0


X = + 3


The O.N. of B is + 3.


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