Make your own carbonated drink using you breath and muscle power.

Stage 1. Breathe out into the canister, replacing the current gas with 17% co2.

Stage 2. Now build up the pressurize with a hand pump, as is done with airguns.

Stage 3. Repeat 1 and 2 several times until pressure is high enough.

Stage 4. Fit apparatus to can and re-carbonate.

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Sorry! I read 17% carbon dioxide in the google result

nitrogen – 78% oxygen – 17% carbon dioxide – 4% other gases – 1%.
-- pashute, Aug 06 2023

Exhaled air is only about 4.4% CO2. Your body doesn't actually convert most of the oxygen.

There are approaches to increasing this, either by removing the nitrogen (I calculate a portable oxygen concentrator should give a CO2 concentration of about 18.9% when used in this manner), or specifically extracting the CO2 - which could yield very pure CO2, but I think would need a much larger machine.
-- Loris, Aug 06 2023


drat. I read 17% carbon dioxide in the google result:

nitrogen – 78% oxygen – 17% carbon dioxide – 4% other gases – 1%.

That's my Hebrew interfering there, and me reading only the words I wanted to read.
-- pashute, Aug 06 2023


It's easily done. I hate that sort of ambiguous list.
-- Loris, Aug 06 2023


If I hold my breath that will result in a higher CO2 output per breath.
-- Voice, Aug 06 2023


I'm going to pretend I'm learning a difficult language and therefore have a right to criticize your efforts. Man, this Swahili is tough.
-- Voice, Aug 06 2023



random, halfbakery