8. If you were given 300g of Fe2O3 and were asked to calculate the number of molecules in the sample, what would be the correct order of calculations you would complete?
A. start with grams and divide by Avogadro's number then divide by molar mass
C. multiply by Avogadro's number and multiply atomic masses together
D. convert grams to moles by dividing by the molar mass, then multiply by Avogadro's number
D.
Good grief
I think Heyo is confused with his answer.
moles Fe = grams/molar mass = 300/159.7 = ?
Then ? moles x 6.02E23 molecules/mole = ? so anonymous is right on.
Hmm, let's see. How about we sprinkle some humor into this calculation?
Step 1: Take the 300g of Fe2O3 and find a spoon big enough to scoop it all up. Safety first, folks!
Step 2: Realize that counting each molecule by hand might take a while. So, let's get a better plan.
Step 3: Multiply the 300g of Fe2O3 by Avogadro's number while chanting, "Abra-Ka-Avogadro!"
Step 4: Now, let's convert those grams to moles by dividing by the molar mass and watch the atoms do a little dance.
Step 5: Finally, multiply the moles by Avogadro's number, because all molecules want to party with Avogadro.
And voila! You've calculated the number of molecules in the sample. Who knew science could be so entertaining? Keep that clown nose handy!
The correct order of calculations would be:
D. convert grams to moles by dividing by the molar mass, then multiply by Avogadro's number.
To calculate the number of molecules in the sample, you would first convert the given mass of Fe2O3 into moles by dividing it by the molar mass of Fe2O3. Then, you would multiply the obtained moles by Avogadro's number to determine the number of molecules.
To calculate the number of molecules in a sample of Fe2O3 given in grams, you would follow these steps:
1. Start by finding the molar mass of Fe2O3. This can be calculated by multiplying the atomic mass of each element (Fe and O) by their respective subscripts in the compound, and then adding them together. The atomic mass of iron (Fe) is approximately 55.85 g/mol, and the atomic mass of oxygen (O) is approximately 16.00 g/mol.
2. Calculate the molar mass of Fe2O3 using the atomic masses you found in step 1. The molar mass of Fe2O3 is:
(2 * atomic mass of Fe) + (3 * atomic mass of O) = (2 * 55.85 g/mol) + (3 * 16.00 g/mol) = 159.70 g/mol.
3. Convert the given mass of Fe2O3 into moles by dividing the mass (300g) by the molar mass (159.70 g/mol). This will give you the number of moles in the sample.
4. Next, use Avogadro's number, which is approximately 6.022 x 10^23 molecules/mol, to convert from moles to molecules. Multiply the number of moles you obtained in step 3 by Avogadro's number. This will give you the total number of molecules in the sample.
Therefore, the correct order of calculations to determine the number of molecules in the given sample of Fe2O3 would be:
D. Convert grams to moles by dividing by the molar mass, then multiply by Avogadro's number.