NY Chemistry Regents Exam Jan 2023

52 Determine the oxidation state of chromium in K2CrO4.

We can look at the periodic table to find oxidation numbers for K and O. K is +1 and O is -2.

Next we can make an equation to find Cr oxidation number. The overall charge of the molecule is 0 since the charge is not shown.

2(+1) + X + 4*(-2) = 0

X is the oxidation number for Cr

We get, 2+x-8 = 0

x-6=0

x=6

The oxidation number of Cr is +6