Oxidation state of carbon in Be2C
Let oxidation state of carbon = x
∴ 2(+2) + x = 0
4 + x = 0
x = -4
∴ The oxidation state of carbon in Be2C = -4
Oxidation state of carbon in Al4C3
Let oxidation state of carbon = x
∴ 4(+3) + 3x = 0
12 + 3x = 0
3x = -12
∴ The oxidation state of carbon in Al4C3 = -4