To calculate the average atomic weight, each exact atomic weight is multiplied by its percent abundance, then, add the results together. If the natural abundance of 63Cu is assigned x, the natural abundance of 65Cu is 1-x (the two abundance always add up to 1). So the solution is: (63)(x)+(65)(1-x) = 63.55, 63x+65-65x=63.55, x=0.725=72.5%. The natural abundance of 63Cu is 72.5%, that of 65Cu is 1-72.5%=27.5%.
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Bikes that are kept outside are not used as often, speeding up the chemical reaction of metal rusting.
Heat energy from the sun slows down the chemical reaction of the metal rusting.
Moisture and oxygen cause oxidation, which speeds up the chemical reaction of the metal rusting.
Wind energy outside speeds up the chemical reaction of the metal rusting.
Answer:
D, because he discovered electrons
Explanation:
