Can a printer print white color?
You will not get anything on the paper with a basic CMYK inkjet or laser printer. The CMYK color mixing is subtractive, meaning that it requires the base that is being colored to have all colors (i.e., White) So that it can create color variation through subtraction:
White - Cyan - Yellow = Green
White - Yellow - Magenta = Red
White - Cyan - Magenta = Blue
White is represented as 0 cyan, 0 yellow, 0 magenta, and 0 black - effectively, 0 ink for a printer that simply has those four cartridges. This works great when you have white media, as "printing no ink" simply leaves the white exposed, but as you can imagine, this doesn't work for non-white media.
If you don't have a base color to subtract from (i.e., Black), then it doesn't matter what you subtract from it, you still have the color Black.
As others are pointing out, there are special printers which can operate in the CMYW color space, or otherwise have a white ink or toner. These can be used to print light colors on top of dark or otherwise non-white media.
You might also find my answer to a different question about color spaces helpful or informative.
It depends on the printer. If it's an inkjet printer, the mixture of these colors will just soak into the black paper. It will be much like using a dark colored marker pen on black paper.
With a laser printer, it's different, because it works by depositing a plastic powder on top of the paper, and melting it on, like the toppings of a pizza.
This property of the laser printer method makes it possible to do toner transfers: to print something onto transfer paper, and then transfer the toner from the paper onto an object. I have etched circuit boards this way, by transferring toner to copper, that toner being thick enough to resist the etching solution.
Colored toner baked onto dark paper should therefore be visible, but no combination of the toner colors will produce white.
The Japanese company ALPS produced a printing technology which could render unusual colors, like white.
To get white ink you will need a white ink cartridge, unlike black ink which can be mixed from the other three colours if needed. If you also take into account that majority of people want to print black and/or colour on white paper, you can understand why white is not a common colour.
Ink/Paint is inverse to light when it comes to white and black.
With light if we mix prime colours we get white light and if we remove all colours we get black, with ink/paint if we mix all colours we get black and if we take it all away we get white.
So if you look at print cartridge the only way it can generate white is not to spray any ink. Otherwise all other colours are made by mixing the standard colours in various degrees
This is obviously a very simple explanation, but feel free to read up more on the internet about how inks and light work :-)
INK: https://en.wikipedia.org/wiki/CMYK_color_model
LIGHT: http://sciencelearn.org.nz/Contexts/Light-and-Sight/Science-Ideas-and-Concepts/Colours-of-light