how many moles of oxygen are needed to reactwith 100g of sodium to produce sodium oxide.can you please write the answer and the and the chemical reaction...
2007-03-07 01:57:20 · 3 answers · asked by aly 1 in Science & Mathematics ➔ Chemistry
The correct way to write the equation is:
4Na + O2 --> 2Na2O
There should NEVER be fractions in your balanced equation!
2007-03-07 02:19:10 · answer #1 · answered by Dr Dave P 7 · 0⤊ 0⤋
Sodium is group 1, therefore, it forms the cation Na(+). The oxide anion is formally, O(2-), therefore, the reaction is as follows:
2Na + 1/2 O2 --> Na2O
So, Na + 1/4O2 ---> 1/2Na2O
Therefore, a quarter of a mole of O2 is needed to react one mole of Na.
How many moles of Na in 100g? Na has a molar mass of 23 g/mol, ie, 1 mole of Na weighs 23 g.
So, 100 g is 100/23 = 4.35 moles.
Since you only need 1/4 as many moles of O2 as you have of Na, divide 4.35 by 4. This gives 1.09 moles of O2.
Remember, that's 1.09 moles of oxygen MOLECULES (O2). If the question asks how many moles of oxygen atoms you need, it's twice the number of molecules, since each molecule contains two atoms.
2007-03-07 10:09:53 · answer #2 · answered by Ian I 4 · 0⤊ 0⤋
?moles Na=100g Na x molar mass of sodium=# moles in Na
2Na + O2 ---> Na2O2
#moles O= (#moles Na x 1mole O)/2 mole Na
2007-03-07 10:08:39 · answer #3 · answered by gladiatorghost007 3 · 0⤊ 0⤋