A calcium atom has {Fill in the blank} valence electrons. It needs to transfer {Fill in the blank} electrons to oxygen to have a full outer shell. An oxygen atom has {Fill in the blank} valence electrons. It needs to accept {Fill in the blank} electrons from calcium to have a full outer shell. After the transfer of electrons, calcium becomes an ion with a charge of {Fill in the blank} and oxygen becomes an ion with a charge of {Fill in the blank}.
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You are attempting to recrystallize a crude product mixture. you add the appropriate amount of hot solvent and are allowing the solution to slowly cool to room temperature. however, at room temperature no crystals have appeared, which of the following methods should be used to induce crystallization? choose all correct answers. a) place the flask in an ice bath. b) swirl the contents of the flask. c) add a small seed crystal of the desired product. d) scratch the inside of the glassware using a stir rod. it can be multiple choices