2006-09-09 02:09:56 · 7 answers · asked by blah blah 1 in Science & Mathematics ➔ Chemistry
in
excess oxygen
2006-09-09 04:45:53 · update #1
If this is in reference to the burning of metallic magnesium in an oxygen atmosphere to give magnesium oxide, then there might be some problems.
"2.70 moles of magnesium in exces"? How large an excess? If there is no oxygen present, then no magnesium oxide will be formed. If there is only a few atoms of magnesium in excess, then there would be no measurable difference in the mass of the product if the magnesium was not in excess, but the oxygen was in excess.
From the balanced equation:
2Mg + O2 --> 2MgO
For every 24.31 grams of Magnesium, the most Magnesium oxide you can get would be 40.31 grams (one mole of Mg give one mole of MgO).
If oxygen was in excess, the 2.70 moles of Mg would give:
2.70 moles X 40.31 g/mole = grams of MgO
Divide this by 1000 g/kg to give kilograms of product.
2006-09-09 02:21:31 · answer #1 · answered by Richard 7 · 65⤊ 0⤋
Since there is an excess of Magnesium then we would have to know how much oxygen was allowed to react with the Magnesium to know how many moles of Magnesium Oxide was formed.
2006-09-09 02:13:31 · answer #2 · answered by rscanner 6 · 0⤊ 2⤋
See my answer to your previous question. I'm assuming you really mean in excess oxygen, since you have a fix number of moles of Mg.
Since you already have the moles of Mg, you just need to recognize and determine the molar mass of MgO, and do the calculation the same way.
The general steps in this kind of problem are:
mass limiting reactant -->moles reactant-->moles product-->mass product
2006-09-09 02:20:47 · answer #3 · answered by hcbiochem 7 · 0⤊ 0⤋
24 gm or 1 moles of magnesium gives= 40 gm or 1 mole of magnesium oxide
2.7 moles of magnesium will give = 2.7x40 grams
=108 grams
= 108/1000 kg=0.108kg
2006-09-09 03:55:41 · answer #4 · answered by Amar Soni 7 · 0⤊ 1⤋
if magnesium reacts with oxygen (as u have not suggested with what mg reacts) acc to balanced equation Mg + O2 =MgO a million mole of Mg provides magnesium oxide=1mole 2.7 " " " " " " =2.7 " =(2.7 *24)/one thousand=0.0648 kg.
2016-12-15 05:07:43 · answer #5 · answered by Anonymous · 0⤊ 0⤋
2Mg + O2 = 2MgO
Therfore no of moles of Mg = no of moles of MgO cuz the coefficient in front of Mg and MgO is the same.
Thus, MgO ------ 2.70moles x 40.31g/moles=108.837g
Kilograms=0.108837
2006-09-09 04:28:15 · answer #6 · answered by Fatima A 3 · 0⤊ 1⤋
2Mg + O2 -> 2MgO
mole ratio: 2Mg: 2 MgO
so- no. of moles of MgO formed=2.70
mass of MgO formed=2.70x (24.3+16)=108.81g=0.10881g
2006-09-09 05:11:59 · answer #7 · answered by alien 1 · 0⤊ 1⤋