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Answer:
21.182 g
Explanation:
There are about (6.0)(10^23) atoms in one mole of a substance, so the given sample has about 0.333 mol of Cu.
The atomic mass of Cu is 63.546 g/mol, meaning that the answer is about <u>21.182</u><u> </u><u>g</u>
H.
represents hydrogen element. under non metal classification.
for others, you'll find them under metal element classification.
The minimum volume of 0.2M sodium sulfide that will precipitate out aluminum from 50.0 mL, 0.25 M aluminum nitrate would be 0.094 L or 94 mL
<h3>Stoichiometric calculation</h3>
From the equation of the reaction:

Mole ratio of Na2S and Al(NO3)3 = 3:2
Mole of 50.0 mL, 0.25 M Al(NO3)3 = 50/1000 x 0.25
= 0.0125 mole
Equivalent mole of Na2S = 3/2 x 0.0125
= 0.0188 mole
Volume of 0.2M, 0.0188 mole Na2S = 0.0188/0.2
= 0.094 L or 94 mL
More on stoichiometric calculations can be found here: brainly.com/question/8062886