Question

Aluminum oxide, Al2O3, is used as a filler for paints and varnishes as well as in the manufacture of electrical insulators. Calculate the number of moles in 47.51 g of Al2O3.

Answer 1

To calculate the number of moles in 47.51 g of Al₂O₃, use the molar mass of Al₂O₃. The molar mass of Al₂O₃ is 101.96 g/mol, so the number of moles is approximately 0.466 moles.

Step-by-step explanation:

To calculate the number of moles in 47.51 g of Al₂O₃, we need to use the molar mass of Al₂O₃. The molar mass of Al₂O₃ is calculated by adding the atomic masses of aluminum (Al) and oxygen (O) in the compound.

The atomic mass of Al is 26.98 g/mol, and the atomic mass of O is 16.00 g/mol. So, the molar mass of Al₂O₃ is 101.96 g/mol.

Next, we use the formula: number of moles = mass / molar mass. Plugging in the given values, we have: number of moles = 47.51 g / 101.96 g/mol. Evaluating this expression gives us the number of moles in 47.51 g of Al₂O₃ as approximately 0.466 moles.

Answer 2

the number of moles in 47.51 g of Al2O3.

let M is the molar mass
and n the number of moles

we know that M = m / n where m is the mass
so we can get n =m/M

M(Al2O3)=2*27+3*16=102

n=74.51/102= 0.46 mole

the answer is
0.46 mole