Analyzing False Statements about Orbitals

[a.a]

I was able to work through most of them myself but am haveing problems with the following, for some I simply don't understand the statement it self. Any help appericiated.
Pick the false statements out of the following:


a. Different p orbitals with the same value of the principal quantum number have different orientations in space.
b. Only three different orientations are possible for 3d orbitals.
c. A dxy orbital has maximum electron density along the x and y axes directions.
d. For the hydrogen atom, a 3d orbital is of higher energy than a 4s orbital.
e. For helium atom, a 3d electron is of higher energy than a 3s electron.

I think b, c, and d are false, but am very unsure.

 

[a.a]

I just read-up on the topic a bit more, I now think that only b and c are false. Can someone pleasr verify?

 

[baba89]

I can confirm that b, c, and d are indeed false statements. Let me explain why:

a. This statement is true. Different p orbitals with the same principal quantum number (n) have different orientations in space. This is because the p orbital has three different sublevels (px, py, and pz) which correspond to the three different directions in space.

b. This statement is false. There are actually five different orientations possible for 3d orbitals, not just three. These include dxy, dyz, dzx, dx2-y2, and dz2.

c. This statement is also false. A dxy orbital does not have maximum electron density along the x and y axes directions. Instead, it has two lobes that are directed between the x and y axes.

d. This statement is false. In the hydrogen atom, a 3d orbital is actually of lower energy than a 4s orbital. This is due to the different shapes and orientations of these orbitals.

e. This statement is true. For helium atom, a 3d electron is indeed of higher energy than a 3s electron. This is because the 3d orbital is a higher energy sublevel than the 3s orbital.

I hope this explanation helps to clarify any confusion you may have had about these statements. It's important to carefully examine and understand statements about orbitals, as they play a crucial role in understanding the behavior of atoms and molecules.