If 6.50 g of the unknown compound contained 0.217 mol of C and 0.433 of H, how many moles of oxygen,O, were in the sample?

0.216 mole

g C = 0.217 mol C x atomic mass C

g H = 0.436 mol?(no unit) x atomic mass H
gC + gO + gH = 6.50 g.

To find the number of moles of oxygen (O) in the sample, we need to subtract the moles of carbon (C) and hydrogen (H) from the total moles in the compound.

Given:
Mass of the unknown compound = 6.50 g
Moles of carbon (C) = 0.217 mol
Moles of hydrogen (H) = 0.433 mol

To calculate the moles of oxygen (O), we can use the concept of the law of conservation of mass. Since the compound is composed of elements C, H, and O, the total mass of the compound should be equal to the sum of the masses of its individual elements.

1. Calculate the total mass of carbon (C):
Using the atomic mass of carbon (12.01 g/mol):
Mass of carbon (C) = Moles of carbon (C) x Atomic mass of carbon (C)
Mass of carbon (C) = 0.217 mol x 12.01 g/mol

2. Calculate the total mass of hydrogen (H):
Using the atomic mass of hydrogen (1.01 g/mol):
Mass of hydrogen (H) = Moles of hydrogen (H) x Atomic mass of hydrogen (H)
Mass of hydrogen (H) = 0.433 mol x 1.01 g/mol

3. Calculate the total mass of the compound:
Total mass of the compound = Mass of carbon (C) + Mass of hydrogen (H) + Mass of oxygen (O)

4. Calculate the mass of oxygen (O):
Mass of oxygen (O) = Total mass of the compound - Mass of carbon (C) - Mass of hydrogen (H)
Mass of oxygen (O) = 6.50 g - (Mass of carbon (C) + Mass of hydrogen (H))

5. Convert the mass of oxygen (O) to moles:
Moles of oxygen (O) = Mass of oxygen (O) / Atomic mass of oxygen (O)

Now you can calculate the moles of oxygen (O) using the provided information.

To determine the number of moles of oxygen (O) in the sample, we need to use the given information about the amounts of carbon (C) and hydrogen (H) present in the compound.

First, let's calculate the number of moles of carbon (C):
Given:
Mass of the compound = 6.50 g
Molar mass of carbon (C) = 12.01 g/mol

To find the moles of carbon, we divide the mass of carbon by its molar mass:
Moles of C = Mass of C / Molar mass of C
Moles of C = 0.217 mol

Next, let's calculate the number of moles of hydrogen (H):
Given:
Mass of the compound = 6.50 g
Molar mass of hydrogen (H) = 1.01 g/mol

To find the moles of hydrogen, we divide the mass of hydrogen by its molar mass:
Moles of H = Mass of H / Molar mass of H
Moles of H = 0.433 mol

Now, we need to determine the number of moles of oxygen (O). To do this, we subtract the moles of carbon and hydrogen from the total number of moles in the compound.

Total moles in the compound = Moles of C + Moles of H + Moles of O
Total moles in the compound = 0.217 mol + 0.433 mol + Moles of O

Since we know the total mass of the compound is 6.50 g, and we have calculated the moles of carbon and hydrogen, we can find the moles of oxygen:

Total mass of the compound = Mass of C + Mass of H + Mass of O

Rearranging the equation to solve for the moles of oxygen:

Moles of O = Total moles - (Moles of C + Moles of H)
Moles of O = Total moles - (0.217 mol + 0.433 mol)
Moles of O = Total moles - 0.650 mol

Given that the total number of moles in the compound is not given in the question, it is difficult to determine the exact number of moles of oxygen. However, if you have additional information or can provide the total moles in the compound, we can help you calculate the moles of oxygen.