Given the balanced equation representing a reaction : 2Fe+ 3Cu^2+ --> 2Fe^3+ +3Cu
When the iron atoms lose six moles of electrons, how many moles of electrons are gained by the copper ions?
(1) 12 moles
(2) 2 moles
(3) 3 moles
(4) 6 moles
how would i even start solving a problem like this?
It isn't a hard question if you remember that in a balanced equation the number of mols electrons lost ALWAYS equals the mols gained.
There is a second but more work way of doing it like this.
Oxidation state Fe on the left is 0. On the right is +6 (2*3+ = 6+) and going from 0 to 6+ Fe must have lost 6e.
Cu on the left is 6+ (3*2+= 6). On the right Cu is 0. Going from 6+ to 0 Cu must have gained 6e.
How 'bout that?
now I understand. thank you (:
Ah, nothing like a good chemistry question to start the day! Let me assist you with some electrifying humor.
To solve this problem, we need to use the stoichiometry of the balanced equation. We're given that 2 moles of Fe (iron) atoms lose 6 moles of electrons. So, if we compare this to the balanced equation, we can see that 2 moles of Fe atoms is equivalent to 6 moles of electrons.
Now, since the ratio of Fe to Cu^2+ in the balanced equation is 2:3, we can conclude that for every 2 moles of Fe atoms, 3 moles of Cu^2+ ions gain a certain number of electrons. Therefore, using our electrifying logic, the answer is (3) 3 moles.
Remember, chemistry can be fun, especially when you're zapping electrons left and right!
To solve this problem, you need to understand how to balance a chemical equation and the concept of stoichiometry.
First, let's look at the balanced equation: 2Fe + 3Cu^2+ -> 2Fe^3+ + 3Cu.
From this equation, we can see that for every 2 moles of iron (Fe) that react, 3 moles of copper ions (Cu^2+) are consumed.
Now, we are told that the iron atoms lose 6 moles of electrons. Since each ion has a charge of +2, this means that 6 moles of electrons are required to convert the iron atoms from Fe to Fe^3+.
From the balanced equation, we know that 2 moles of iron (Fe) are required to obtain 3 moles of copper ions (Cu^2+). Therefore, each mole of copper ion (Cu^2+) corresponds to (6/2) = 3 moles of electrons.
So, the correct answer is (3) 3 moles.
thanks so much. so you would always count up the oxidation states and see how much one side needs to equal the other?
That's right. In fact that is the whole concept behind balancing redox equations. You count up the electrons lost from one side to the other; count up electrons gained from one side to the other, then multiply by whatever numbers you need to make electrons gained equal electrons lost. That MAKES the reduction and oxidation parts balance and with those numbers in the bank so to speak you can easily balance the non-redox portion.
In addition, for this problem, they already tell you how many were lost so you don't even need to count them up. You know straight away that is 6 gained.