I overdid it. I wanted to make sure that she was going to die the first time. I used a plastic kitty litter container (the box that you can buy tons of litter in that have lids) but any airtight container will work. Then, I put 1/2 cup baking soda in a sandwich sized rubbermaid storage tub (for the volume of liquid that bubbled I needed a bigger container). Then, I put her on a couple of paper towels on the other side. When I was a close to ready I was ever going to be I poured around 1/2 cup vinegar in the tupperware and shut the lid. I put our gallon sized container of vinegar on top to ensure a tight fit with the lid. Finally, I set the timer for 5 minutes as I had read at one of the veterinary medicine euthanasia sites that it was a good time to make sure it had taken effect. I never heard a peep out of the box and when I came back it was done. (On a side note, I spent those 5 minutes snuggling the other 5 chicks.) She is currently in the freezer ina ziplock awaiting plantation into my garden.