How many oxygen atoms are in 10.3 g of CuSO4*5H2O?
What is the mass percent of carbon in C(12)H(22)O(11)?
1. divide by molar mass of CuSO4*5H2O to convert to mole and multiply by avocado's number (6.022 × 10^23) to find how many atoms there are
2. [12(12.01)/total mass] x 100%
1. (10.3g CuSO4*5H2O)(1 mole /____M.M.CuSO4*5H2O)(6.022 × 10^23 atoms 6.022 × 10^23/ 1 mole)
notice all the units cancel except for atoms
I disagree with TutorCat with regard to #1. I agree with what is there; however, the answer provided with that calculation will be the number of molecules of CuSO4*5H2O. The question asks for number of oxygen atoms. Therefore, take the number in TutorCat's answer, and multiply by 9 to obtain the number of oxygen atoms.
Also, I would like to make a correction. It's Avogadro's number and not avocado's number. This is a man's name, not a fruit.
opps! I overlooked the oxygen part.
To determine the number of oxygen atoms in 10.3 g of CuSO4·5H2O, we need to first calculate the molar mass of CuSO4·5H2O. Then, we can use the Avogadro's number (6.022 × 10^23) to convert the mass into the number of moles. Finally, we can use the stoichiometry of the compound to find the number of oxygen atoms.
Step 1: Calculate the molar mass of CuSO4·5H2O.
Cu has a molar mass of 63.55 g/mol.
S has a molar mass of 32.07 g/mol.
O has a molar mass of 16.00 g/mol.
H has a molar mass of 1.01 g/mol.
To calculate the molar mass of CuSO4·5H2O, we sum up the molar masses of each component:
Molar mass of CuSO4·5H2O = (63.55 g/mol) + (32.07 g/mol) + (4 * 16.00 g/mol) + (5 * [(2 * 1.01 g/mol) + (16.00 g/mol)]) = 249.69 g/mol
Step 2: Convert the mass into moles.
Number of moles = mass / molar mass = 10.3 g / 249.69 g/mol ≈ 0.0413 mol
Step 3: Calculate the number of oxygen atoms.
Since there are 4 oxygen atoms in one CuSO4·5H2O molecule, we can multiply the number of moles by 4 to get the number of oxygen atoms.
Number of oxygen atoms = (0.0413 mol) * 4 = 0.1652 moles
Therefore, there are approximately 0.1652 moles (or 9.958 × 10^22) oxygen atoms in 10.3 g of CuSO4·5H2O.
Now let's move on to the second question.
To determine the mass percent of carbon in C12H22O11, we need to calculate the molar mass of C12H22O11 and the molar mass of carbon. Then we can use the formula to find the mass percent.
Step 1: Calculate the molar mass of C12H22O11.
C has a molar mass of 12.01 g/mol.
H has a molar mass of 1.01 g/mol.
O has a molar mass of 16.00 g/mol.
Molar mass of C12H22O11 = (12.01 g/mol * 12) + (1.01 g/mol * 22) + (16.00 g/mol * 11) = 342.34 g/mol.
Step 2: Calculate the molar mass of carbon.
Since C12H22O11 contains 12 moles of carbon, the molar mass of carbon is 12.01 g/mol.
Step 3: Calculate the mass percent of carbon.
Mass percent of carbon = (molar mass of carbon / molar mass of C12H22O11) x 100 = (12.01 g/mol / 342.34 g/mol) x 100 ≈ 3.51%.
Therefore, the mass percent of carbon in C12H22O11 is approximately 3.51%.