How many moles are present in 288 grams of oxygen?

Answer 1

Oxygen is a diatomic gas, so a molecule of oxygen contains two oxygen atoms.

One oxygen atom has an atomic weight of 16.00 amu (Atomic Mass units), so diatomic oxygen has a molecular weight of 16.00 × 2 or 32.00 amu

amu (a.k.a., molar mass) are in units of grams/mol, so by dividing:

8.0 g O2 ÷ 32.00 g/mol O2 = 0.25 mol O2

One mol contains 6.022 × 1023 molecules (Avogadro's number), which can be multiplied by our 0.25 mol O2 to get the number of moles in 8.0 grams O2:

0.25 mol O2 × (6.022 × 1023) = 1.5055 × 1023 molecules

Don't forget to round to two significant figures (limited in precision by the 8.0 grams given):

There are 1.5 x 1023 molecules of O2 in 8.0 grams of O2

Answer 2

Molar weight of oxygen (O2), Mw = 2x16 = 32 g/mol

The number of molecules in one mol of O2 is equal to avogadro's number, Na = 6.022x10^23 molecules per mol of O2.

The number of molecules per gram of O2 is then equal to the number of molecules per mole of O2 divided by the molar weight of O2, Nw = 6.022x10^23/32 = 1.882x10^22 molecules per gram O2.

For 8 grams of O2 the number of molecules is equal to the number of molecules per gram multiplied by the amount of grams of O2, N = 1.882x10^22 x 8 = 15.056x10^22 molecules

Answer 3

If you are talking about moles of the atom, then the relative atomic mass of oxygen is 16, so 4/16 is 0.25. However, all the oxygen around us is diatomic, so if you are talking about that, then the relative molecular mass is 32; therefore 4/32 is 0.125. If you actually talking about individual molecules, times those answers by 6.02*10^23 (Avogadro's constant) to get:

1.505*10^23 for the elemental form of Oxygen

7.525*10^23 for the diatomic normal form of Oxygen found in air.

Answer 4

Avogadro's Number, 6.022 X 1023, is the number of atoms per gram molecular mass. The gram atomic mass of oxygen is 15.9994. Therefore, 4 grams of oxygen contains (6.022 X 1023 ) 4/15.9994 or 1.5 X 1023 atoms. At standard temperature and pressure, oxygen exists as diatomic molecules. Therefore, the number of molecules is 8 X 1022 molecules, to the justified number of significant digits, if limited by the single digit of the datum 4 grams. If the 4 is considered exact, the number of molecules would be 7.530 X 1022, limited by the number of significant digits in the value used for Avogadro's Number.

Answer 5

Molecular mass of O2 = 32.0

Amount of O2 = 8.0/32.0 = 0.25mol

1 mol of O2 contains 6.02 x 1023 molecules (avogadro constant).

Therefore 0.25mol of O2 contains 0.25 x 6.02 x 1023 = 1.51 x 1023 molecules

Answer 6

~16 grams of oxygen per mole. 3 atoms of oxygen per molecule of ozone, so:

8.0/(16*3) = 1/6 of a mole of ozone molecules.

Answer 7

1 mole of oxygen = 16 grams

8/16 = 0.5 moles

Answer 8

3.01*10^23 atoms . It's about half a mole.

Note that doesn't count molecules. Oxygen is normally O2 or O3.

Answer 9

288 g oxygen is equivalent to 9 moles.

Answer 10

8,25 grams of O (atomic) is equal to 0,515 moles.