Answer:
-753kJ of energy are involved
Explanation:
Based on the reaction:
Fe₂O₃(s) + 2 Al(s) → Al₂O₃(s) + 2 Fe(s) ΔH°rxn = -852 kJ
<em>When 2 moles of Fe are produced, there are released -852kJ.</em>
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98.7g of Fe are:
98.7g Fe × (1mol / 55.845g) = 1.767 moles of Fe
If 2 moles of Fe are producen when -852 kJ of energy are involved, 1.767 moles of Fe envolved:
1.767mol × (-852kJ / 2mol Fe) = <em>-753kJ of energy are involved</em>
The answer is 2.78 moles of Si
Answer:
There’s a high need for energy storage and are very expensive. Renewable energy is also not always available because some need sun while others need wind.
Explanation:
a. The unit cell is the smallest group of atom which have overall symmetry of a crystal, and from which is the entire letters can be buled built up by repetition in 3 dimensions.
b. The volume(v) of the unit cell is equal to the cell edge length (a)cubed.
c. density of polonium is 9.32g/cm3.
