Teh molar mass of a compund is 92.0g/mol. Analysis of the compound indicates that it contains .606g Nitrogen and 1.339g Oxygen. Find its molecular formula? I was wondering can oyu explain how you received your answer
Convert grams to mols.
mols nitrogen = 0.606/14 = 0.0430
mols oxygen = 1.339/16 = 0.0837
So the formula is
N0.0430O0.0837
BUT we know that elements combine in the ratio of small whole numbers; therefore, we want to convert those subscripts to small whole numbers. How can we do that? We can divide the smaller number by itself which forces it to be 1.00. Then to keep the equality between the atoms we divide the other number by that same divisor. Like so.
0.0430/0.0430 = 1.00 = N
0.0837/0.0430 = 1.95 = O which is close enough to round to 2.
The formula is NO2.
Thanks very much I kinds figured that is how it goes down
Yes, you got it right! To determine the molecular formula, we need to convert the given masses of nitrogen and oxygen into moles. This is done by dividing the masses by the respective molar masses.
For nitrogen:
Mass of nitrogen = 0.606 grams
Molar mass of nitrogen = 14 grams/mol (from the periodic table)
Moles of nitrogen = 0.606 grams / 14 grams/mol = 0.0430 mol
For oxygen:
Mass of oxygen = 1.339 grams
Molar mass of oxygen = 16 grams/mol (from the periodic table)
Moles of oxygen = 1.339 grams / 16 grams/mol = 0.0837 mol
Now, we express the number of moles as subscripts in the molecular formula. Thus, the formula becomes N0.0430O0.0837.
Since elements combine in whole number ratios, we need to convert these subscripts to the nearest whole numbers. To do this, divide both subscripts by the smaller subscript, which in this case is 0.0430.
0.0430 / 0.0430 = 1.00 for nitrogen (N)
0.0837 / 0.0430 = 1.95 (approximately) for oxygen (O)
Rounding to the nearest whole number, we get 2 for oxygen (O). Thus, the molecular formula is NO2.
I hope this clears up how the answer was obtained! Let me know if you have any more questions.