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Question

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An emergency breathing apparatus often placed in mines works via the following chemical reaction: 4KO2(s) + 2CO2(g) to make 2K2CO3(s) + O2(g)

If the oxygen supply becomes limited or if the air becomes poisoned, a worker can use the apparatus to breath while exiting the mine. Notice that the reaction produces O2, with can be breathed, and absorbs CO2, a product of respiration. What minimum amount of KO2 is required for the apparatus to produce enough oxygen to allow the user 15 minutes to exit in an emergency? Assume that an adult consumes approximately 4.4g of oxygen in 15 minutes of normal breathing.

4.4g of O2? figure the moles of O2, then

Look at the balanced equation: it takes four times that amount of moles of O2 of KO2. What is the mass of that?