Reducing Agents and their relative strengths

[kc262]

Homework Statement

This question should be quite simple. Yet I am getting it wrong. It it's really frustrating. Can someone see what I'm doing wrong? Or maybe it's because my concepts are messed up.

Assuming standard conditions, and considering the table of standard reduction potentials for half-reactions, given in your text, rank the following species according to their relative strength as reducing agents. For example, the most powerful reducing agent would be given rank "1", and the least "6".

Homework Equations

A link for a Standard reduction potential table is here: http://www.jesuitnola.org/upload/clark/refs/red_pot.htm

The Attempt at a Solution

The order I got was 4,3,2,5,1,6 ( F-, Fe2+, I-, Cd, Zn, K)
Reasoning is that the reducing agent is oxidized and therefore loses the electrons. So looking at the standard reduction potential table, I got my voltage values from there, and changed the signs where I needed to. But i keep getting it wrong. Help and a push in the right direction would be fantastic. =]

 

[chemisttree]

...the most powerful reducing agent would be given rank "1", and the least "6".

...The order I got was 4,3,2,5,1,6 ( F-, Fe2+, I-, Cd, Zn, K)

You have fluoride as the fourth strongest reducing agent. It's pretty difficult to remove that electron! (ie. it's a TERRIBLE reducing agent).

You have metallic potassium as the LEAST reducing! That couldn't be more wrong. (unless lithium were also on the list)

You need to start by writing for yourself the reducing half reactions. Only then are you to use the tables...

 

[Blueshift5]

I would say that your reasoning is correct. However, it is important to note that the standard reduction potential table only provides a relative measure of the strength of reducing agents. It is possible that there are other factors at play that could affect the strength of a reducing agent in a specific reaction.

In order to confirm your answer, I would suggest double-checking your calculations and making sure that you are using the correct signs for the standard reduction potentials. It may also be helpful to review the concept of standard reduction potentials and how they are used to determine the relative strength of reducing agents.

If you are still having trouble, I would recommend seeking help from a classmate, professor, or tutor to go over the problem with you and identify any errors. Sometimes, having a fresh perspective can help pinpoint where you may have gone wrong.