Which of the following substances is a compound? A. hydrogen gas B. nitrogen gas C. table sugar D. oxygen gas

An electron moved from shell n = 2 to shell n = 1. what most likely happened during the transition? a fraction of a photon was added. a photon of energy was absorbed. a fraction of a photon was removed. a photon of energy was released.

Use the periodic table to determine how many grams of oxygen would be required to react completely with 859.0 g c2h2

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