A metal M reacts with nitrate ions, 
, in acid conditions.
The products are 
ions, water and nitrogen(II) oxide, NO.
The reacting ratio of M atoms to nitrate ions is 3:2.
What is the value of n in the M
ion?
A 1
B 2
C 3
D 4
The only correct answer is B
A is not correct because 2 nitrate ions have a total drop in
oxidation number of +6 so each M must increase by 2.
C is not correct because 2 nitrate ions have a total drop in
oxidation number of +6 so each M must increase by 2.
D is not correct because 2 nitrate ions have a total drop in
oxidation number of +6 so each M must increase by 2.
