Subject: Is Total breakfast cereal a heterogenous or homogeneous mixture?

In an experiment, we had to crush up Total cereal, add some 
water, then put a bar magnet in the mixture and examine the 
particles on the magnet under a microscope. I think the cereal 
with the water is a heterogenous mixture, but the cereal grain 
itself is a homogenous mixture because iron particles were 
separated out of it on the magnet.  Is my reasoning correct?

Re: Is Total breakfast cereal a heterogenous or homogeneous mixture?