[dipndots]

I had this problem on a test and couldn't figure it out:

Coke is an inexpenive and impure form of carbon that is often used in the industrial preoduction of metals from their oxides. If a sample of coke is 95.0% carbon by mass, determine the mass of coke needed to completely react with 100. tons of an ore that is 3.40% copper (II) oxide by mass to produce copper metal and carbon dioxide? [ 1 ton = 907 kg]

 

[Yggdrasil]

Start with a balanced chemical reaction.

[tinhb]

C + 2CuO -> CO₂ + 2Cu
100 tons = 90700 kg
KMol of C = 0.5 * KMol of Cuo = 90700 * 0.034 / 80 * .5 = 19.27375 kmol
Mass of coke = 19.27375 * 12 * 100 /95 = 243.46 (kg )

[Yggdrasil]

Looks good to me.