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Achange in the number of neutrons in an atom will change an blank . when the number of protons changes in an atom, a new element will form.

Which of the following are good traits of a hypothesis? it will be able to be testedit can predict an outcomeit will explain the observationsall of these

Given the following at 25c calculate delta hf for hcn (g) at 25c. 2nh3 (g) +3o2 (g) + 2ch4 (g) > 2hcn (g) + 6h2o (g) delta h rxn= -870.8 kj. delta hf=-80.3 kj/mol for nh3 (g), -74.6 kj/mol for ch4, and -241.8 kj/mol for h2o (g)