## Cartesian axes [ENDORSED]

Glendy Gonzalez 1A
Posts: 52
Joined: Fri Sep 29, 2017 7:07 am

### Cartesian axes

Can someone please explain Cartesian axes and how can the orientation of orbitals be described using this term, please?
Thank you

Emily Oren 3C
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

### Re: Cartesian axes  [ENDORSED]

The cartesian axes are the x-,y-, and z-axes representing the three physical dimensions. In other words they are directions in space (forward-backward, left-right, and up-down). The orientations of the orbitals are defined along these axes in order to make the math work. There is no "universal" x-axis, but defining the x-axis as a direction that a p-orbital can point allows the atom to be mathematically modelled precisely.
Here's an image of p-orbitals in all three orientations: http://www.chemtube3d.com/images/Alevel-porbitals.jpg

Kourtney Nham 1L
Posts: 20
Joined: Fri Sep 29, 2017 7:04 am

### Re: Cartesian axes

Cartesian axes are simply the axes x, y, and for a third dimension, z. When graphing something, the coordinates indicate where it is on the plane in respect to the axes. This can be used to describe orientation of orbitals. For example, the 2p orbitals are perpendicular to each other and lie along the 3 axes (x, y, z). If you can visualize it, one orbital would be oriented along the x axis (px), another along the y axis (py), and one along the z axis which denotes a 3rd dimension/dept. It's easier if you look up a picture to really conceptualize it!