The balanced chemical reaction would be written as follows:
2Mg + O2 = 2MgO
We are given the amount magnesium to be used in the reaction. This will be the starting point for the calculations. We do as follows:
15.0 g ( 1 mol / 24.31 g ) (2 mol MgO / 2 mol Mg ) (40.31 g / mol ) = 24.87 g MgO formed
Answer: The purpose of flashback is to either move the story forward or reveal information about the character. You can use flashbacks for any number of reasons but its primary purpose is to bridge time, place and action to reveal a past emotional event or physical conflict that affects the character.
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