Oxidation #s For Zn(NO3)2 ?

  • Thread starter BayernBlues
  • Start date
  • Tags
    Oxidation
In summary, the problem involves balancing a redox reaction using the 1/2 reaction method and determining the oxidation numbers for Zn(NO3)2. The oxidation number for Zn is 0 and for H is +1. For N, it is +5 and for O, it is -2 per molecule of NO3. When combining 2 NO3- groups with Zn, it results in an oxidation number of +2 for Zn in order to cancel out the 2- charge from the 2 NO3 groups.
  • #1
BayernBlues
65
0
[SOLVED] Oxidation #s For Zn(NO3)2 ?

Homework Statement



I need to ballance the redox reaction underneath using the 1/2 reaction method but the problem is that I can't figure out the oxidation #s for Zn(NO3)2 and after that, I'm having problems balancing it.

Homework Equations



Zn + HNO3 ---> Zn(NO3)2 + 2NH4NO3 + H2O

The Attempt at a Solution



On the reactants side, the oxidation # for Zn is 0, For H->+1 for N--->+5 for O3--->-2/atom
 
Physics news on Phys.org
  • #2
NO3 should carry it's original Oxidation numbers when becoming Zn(NO3)2 since it's splits from H which carries a +1 charge. That would make NO3- (a -1 oxidation number for the entire ion since you already stated that N=+5 and O=-2 per molecule). Combining 2 NO3- groups with Zn would give Zn an oxidation number of 2+ in order to cancel out the 2- charge from the 2 NO3 groups, which is a common oxidation number for Zn.
 
  • #3


The oxidation number for Zn in Zn(NO3)2 is +2. This can be determined by looking at the overall charge of the compound (which is 0) and the known oxidation numbers for hydrogen (+1), nitrogen (+5) and oxygen (-2). Since there are two nitrate (NO3) molecules, each with a charge of -1, the zinc must have a charge of +2 to balance out the overall charge.

To balance the redox reaction, you can first split it into two half-reactions:

Zn --> Zn2+ + 2e- (oxidation half-reaction)
HNO3 + 3e- --> NH4+ + 3NO3- (reduction half-reaction)

Next, balance the elements other than hydrogen and oxygen in each half-reaction. In the oxidation half-reaction, there is only one zinc atom on each side, so it is already balanced. In the reduction half-reaction, there are 3 nitrogen atoms on the reactant side, but only 1 on the product side. To balance this, add a coefficient of 3 in front of the NH4+ and NO3- ions.

HNO3 + 3e- --> 3NH4+ + 3NO3-

Next, balance the oxygen atoms by adding H2O molecules to both sides of the equation. In the oxidation half-reaction, there are 2 oxygen atoms on the product side, so add 2 H2O molecules to the product side. In the reduction half-reaction, there are now 6 oxygen atoms on the product side, so add 3 H2O molecules to the product side.

HNO3 + 3e- --> 3NH4+ + 3NO3- + 2H2O

Finally, balance the hydrogen atoms by adding H+ ions to the appropriate side. In the oxidation half-reaction, there are now 6 hydrogen atoms on the product side, so add 6 H+ ions to the reactant side. In the reduction half-reaction, there are already 12 hydrogen atoms on the product side, so no additional H+ ions are needed.

HNO3 + 6e- + 6H+ --> 3NH4+ + 3NO3- + 2H2O

Now, the number of electrons on both sides of
 

1. What is the oxidation number for zinc in Zn(NO3)2?

The oxidation number for zinc in Zn(NO3)2 is +2.

2. How do you determine the oxidation numbers for each element in a compound?

Oxidation numbers can be determined by following a set of rules based on the electronegativity and valence electrons of each element in the compound. In general, the more electronegative element will have a negative oxidation number while the less electronegative element will have a positive oxidation number.

3. Why is the oxidation number for zinc in Zn(NO3)2 +2 and not +1?

Zinc is a transition metal that can have multiple oxidation states. In Zn(NO3)2, the overall charge of the compound is 0, and since there are two nitrate ions with a -1 charge each, the zinc ion must have a +2 charge to balance out the charges and maintain a neutral compound.

4. Can the oxidation number for zinc in Zn(NO3)2 change?

Yes, the oxidation number for zinc in Zn(NO3)2 can change depending on the chemical reaction it is involved in. Zinc can have an oxidation number of +2 or +1 depending on the other elements it is reacting with.

5. What is the purpose of knowing the oxidation numbers for elements in a compound like Zn(NO3)2?

Determining the oxidation numbers for elements in a compound allows us to understand the distribution of electrons and the overall charge of the compound. This information is important for predicting the reactivity and behavior of the compound in chemical reactions.

Similar threads

  • Biology and Chemistry Homework Help
Replies
3
Views
3K
  • Biology and Chemistry Homework Help
Replies
4
Views
5K
  • Biology and Chemistry Homework Help
Replies
4
Views
1K
  • Biology and Chemistry Homework Help
Replies
5
Views
1K
  • Biology and Chemistry Homework Help
Replies
1
Views
3K
Replies
2
Views
2K
  • Biology and Chemistry Homework Help
Replies
16
Views
21K
  • Biology and Chemistry Homework Help
Replies
1
Views
3K
  • Biology and Chemistry Homework Help
Replies
2
Views
4K
  • Biology and Chemistry Homework Help
Replies
4
Views
4K
Back
Top