To calculate the molar mass of Al2O3, we first need to find the molar mass of Al and O.

Molar mass of Al:
Al = 27 g/mol

Molar mass of O:
O = 16 g/mol

Now we can calculate the molar mass of Al2O3:
Al2O3 = 2(Al) + 3(O)
Al2O3 = 2(27 g/mol) + 3(16 g/mol)
Al2O3 = 54 g/mol + 48 g/mol
Al2O3 = 102 g/mol

So, the molar mass of Al2O3 is 102 g/mol.

Now we can calculate the mass of 25g of Al in terms of Al2O3:
Al2O3 = Al/Al2O3 M(Al2O3)
Al2O3 = 25g/27 g/mol 102 g/mol
Al2O3 = 94.44g

Therefore, 25g of Al is equivalent to 94.44g of Al2O3.