2al2o3 → 4al + 302
calculate the mass of aluminium that can be formed from
1020 g of aluminium oxide.

They did not study the continental drift

Particle exchange energy though elastic collision , hope this .

Density and pressure

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.