Answer:
Chemical change :has change in mass, heat is needed, new element is formed, hard to reverse.......
Physicalchange:does not have change in mass, heat is not necessary, no new element is formed, easy to reverse
Answer: Bromine is Actually a Halogen!
Explanation: Bromine is in the 7th column of the Periodic Table. It needs that magic 8 valence electrons and it has 7.
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Answer:
21.2 moles.
Explanation:
Hello!
In this case, for the given chemical reaction, we can see there is a 1:4 mole ratio between tetraphosphorous decaoxide and phosphorous; therefore, the following proportional factor provides the requested moles of phodphorous:

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