Fungal laccase, a blue protein found in wood-rotting fungi, is 0.390% Cu by mass. If a fungal laccase molecule contains four copper atoms, what is the molar mass of fungal laccase?
%Cu = mass Cu x 100/molar mass compound.
0.39 = 4*atomic mass Cu*100/x
Substitute for atomic mass Cu and solve for x.
65200
6.51 x 10^4
Helpful but if you were finishing the solutions so that we know the correct answer
To find the molar mass of fungal laccase, we need to calculate the mass of the copper atoms in one molecule of fungal laccase.
Given that fungal laccase is 0.390% Cu by mass, this means that in 100 g of fungal laccase, 0.390 g is copper.
We know that one mole of any element contains Avogadro's number (6.022 × 10^23) of atoms. The molar mass of Cu is 63.55 g/mol.
To find the number of moles of copper in 0.390 g, we can use the formula:
moles = mass / molar mass
moles of Cu = 0.390 g / (63.55 g/mol)
moles of Cu = 0.00613 mol
Since each fungal laccase molecule contains four copper atoms, we need to multiply the number of moles of Cu by four to find the total moles of copper in one molecule of fungal laccase.
moles of Cu in one molecule = 0.00613 mol * 4
moles of Cu in one molecule = 0.0245 mol
Finally, to find the molar mass of fungal laccase, we divide the mass of copper in one molecule by the moles of copper in one molecule:
molar mass = mass of copper / moles of Cu in one molecule
molar mass = 0.390 g / 0.0245 mol
molar mass = 15.92 g/mol
Therefore, the molar mass of fungal laccase is approximately 15.92 g/mol.