When We Breathe We Inhale Oxygen, O₂, and Exhale Carbon

question 72

Multiple Choice

When we breathe we inhale oxygen, O₂, and exhale carbon dioxide, CO₂, plus water vapor, H₂O. Which likely has more mass, the air that we inhale or the same volume of air we exhale? Does breathing cause you to lose or gain weight?

• A)The air we inhale has more mass; breathing causes you to lose weight.
• B)The air we exhale has more mass; breathing causes you to lose weight.
• C)The air we inhale has more mass; breathing causes you to gain weight.
• D)The air we exhale has more mass; breathing causes you to gain weight.

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