4Al 3O2 ---> 2Al2O3 How many moles of aluminum oxide can be formed from 5.2 moles of Al? What mass of Al is required to react with 6.00 moles of oxygen? What mass of Al oxide can be produced from 25.5 g of Al? if the actual yield is 42.5g what is % yield?
2007-11-07 06:10:40 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
4Al + 3O2 --> 2Al2O3
The equation tells you the ratio of moles reacting and being produced. If you are given moles and want the answer in moles, it's a simple ratio problem. If you are given grams you will need to convert to moles first because the coefficients in the balanced equation refer to the ratio of moles, not of grams.
4 moles of Al reacts with 3 moles O2 to yield 2 moles of Al2O3
You have 5.2 moles Al; you will get (5.2 / 4) x 2 moles of Al2O3
(5.2/4)x2 = 2.6 moles Al2O3
6 moles of O2 requires (6/3)x4 moles of Al
(6/3)x4 = 8 moles of Al
8 moles x 27 g per mole = 216 grams
25.5g Al = 0.944 moles Al
0.944 moles Al will yield (2/4)x0.944 moles of Al2O3
(2/4)x0.944 = 0.472 moles Al2O3
0.472 moles x 102 g/mole = 48 g Al2O3
42.5 / 48 = 88.5% yield
2007-11-07 06:27:45 · answer #1 · answered by skipper 7 · 0⤊ 0⤋
Atomic weights: Al=27 O=16 Al2O3=102 O2=32
5.2molAl x 2molAl2O3/4molAl = 2.6 mole Al2O3
25.5gAl x 1molAl/27gAl x 2molAl2O3/4molAl x 102gAl2O3/1molAl2O3 = 48.2g Al2O3
42.5g/48.2g x 100% = 88.1% yield
2007-11-07 06:17:43 · answer #2 · answered by steve_geo1 7 · 0⤊ 0⤋
holy molyy i just took a test with a simular question. and let me tell you it did not come out with a good result.
2007-11-07 06:15:09 · answer #3 · answered by Anonymous · 0⤊ 0⤋
42!
No I'm just kidding... it's really B= x + y35E (51/62.0021)
2007-11-07 06:14:30 · answer #4 · answered by sunshyn1919 5 · 0⤊ 0⤋
yeah.........that's a really good question but don't really know.............SORRY.
2007-11-07 06:14:28 · answer #5 · answered by Big Red 1 · 0⤊ 0⤋