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Question
A 9.020-g sample of an unknown metal M is burned in the presence of excess oxygen, producing the oxide M2O3(s) and liberating 191.5kJ of heat at constant pressure. What is the identity of the metal?
4M(s)+3O2(g)→2M2O3(s)
| Substance |  Hf(kJ/mol) |
| Yb2O3(s) | -1814.6 |
| Tb2O3(s) | -1865.2 |
| Sm2O3(s) | -1823.0 |
| Sc2O3(s) | -1908.8 |
| Y2O3(s) | -1905.3 |
A) Sm
B) Sc
C) Yb
D) Y
E) Tb
Answer
This answer is hidden. It contains 1 characters.
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