Answer:
2. B. 5:3
3. C. mass and atoms only.
Step-by-step explanation:
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2. In this case, according to the given balanced chemical reaction it is possible to realize that the mole ratio of oxygen to carbon dioxide is B. 5:3 since there is a 5 on O2 and a 3 on CO2.
3. In this case, according to the law of conservation of mass it is possible to realize that matter cannot be created nor destroyed; for that reason both mass and atoms must remain unchanged as the reaction takes place; therefore the answer is C. mass and atoms only.
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