What mass of melamine, c3n3(nh2)3, will be obtained from 170.5 kg of urea, co(nh2)2, if the yield of the overall reaction is 77.0 % ?

The balanced chemical reaction is:

CO(NH2)2(l) → HNCO(l) + NH3(g) 
6 HNCO(l) →= C3N3(NH2)3(l) + 3 CO2(g) 

(170.50 kg CO(NH2)2) / (60.0553 g CO(NH2)2/mol) x (1 mol HNCO / 1 mol CO(NH2)2) x 
(1 mol C3N3(NH2)3 / 6 mol HNCO) x (126.1199 g C3N3(NH2)3/mol) x (0.770) = 45.95 kg C3N3(NH2)3

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