Re: What gases occur when you mix 1) baking soda & vinegar 2) Yeast & peroxide?

When you mix baking soda and vinegar you generate the gas carbon dioxide 
(CO2). There is a nice description of this reaction at the following web 
site, which also describes a bunch of fun experiments to do.:

http://www.exploratorium.edu/science_explorer/bubblebomb.html

The second reaction with yeast and peroxide is more complex. Yeast have an 
enzyme catalase which performs the following reaction: 

  2(H2O2) --> 2(H20) + O2

so the gas generated is oxygen (O2)