Answer:

Explanation:
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In this case, given the masses of copper, zinc and lead, it is possible to compute the moles via their atomic masses first:

Now, we compute the atomic percentages as shown below:

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It's a table that has elements private message me I send u a pic of it ...
How many grams of Cu would be needed to react with 2.0 mol HNO3?
<span>by the equation </span>
<span>3Cu + 8HNO3 --> 3Cu(NO3)2 + 2NO + 4H2O </span>
<span>2.0 mol HNO3 reacts with 3/8 ths as many moles of Cu = 0.75 moles of Cu </span>