Change volume (Liters) to moles
21a) 67.2 L SO2
21b) 0.880 L He
21c) 1000 L C2H6

answer: mole of the gas

answer: mole of the gasexplanation:

answer: mole of the gasexplanation: this is because 1 mole of a gas is 22.4dm³, which is use in ideal gas

Radon-222 or rn-222 has a half-life of 3.82 days. to determine the fraction of an original sample of rn-222 that remains unchanged after 7.646 days, we calculate the amount of rn-222 remaining after 7.646 days and divide it with the original amount. using 1 gram as a basis and using half-life calculation methods, we can determine that  0.249 or 0.25  grams of rn-222 will remain, and thus the fraction remaining is 0.25 or 1/4.

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Homogeneoushoped i