Answer:
open system
Coffee held in a cup is an open system because it can exchange matter water vapors and energy heat with the surroundings.
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Answer:
<em>One mole of anything is 6.022×1023 everythings, including atoms. Multiply the moles Fe by 6.022×1023 atoms/mol. 3.77mol Fe ×6.022×1023atoms Fe1mol Fe =2.27×1024 atoms Fe rounded to three significant figures.</em>
Answer:
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Explanation:
Hello!
In this case, since calcium's oxidation state when forming ionic bonds is +2 and sulfur's oxidation state when bonding those bonds is -2, for the required formula we write:
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Now, since they have the same charge number, we infer the ionic compound formed when they bond is calcium sulfide:
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