Hey there!
Cu(CN)₂
Find the molar mass.
Cu: 1 x 63.546 = 63.546
C: 2 x 12.01 = 24.02
N: 2 x 14.07 = 28.14
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115.706 grams
The mass of one mole of Cu(CN)₂ is 115.706 grams.
We have 4 moles.
115.706 x 4 = 463
4.00 moles of Cu(CN)₂ has a mass of 463 grams.
Hope this helps!