This happens sometimes. The Chromebook doesn't seem to turn on even though everything seems okay. These steps usually fix it:
Verify that the charger and power outlet are working:
Double-check that the outlet is working by plugging another item into that outlet. If that new item doesn't work, try plugging your Chromebook charger into a different outlet.
Unplug your charger from the wall and plug it in again (it may look like it's plugged in but it may be loose and not making a solid connection)
If you have a two piece charger (with a power brick in the middle), unplug the cord from the power brick and plug it back in again (it may look like it's plugged in but it may be loose and not making a solid connection)
Unplug your charger from the Chromebook and plug it in again (it may look like it's plugged in but it may be loose and not making a solid connection)
Most Chromebooks have two charging ports. Plug the charger into the other charging port.
After following the above steps, does the power light come on when the charger is plugged into the Chromebook and the wall outlet?
Hold the power button down for 10-15 seconds to force the Chromebook to power off
If the power light is on but the screen is dark, you will know that the Chromebook has powered off once the power light goes off
Wait a few seconds then press the power button again to turn back on
Allow 30 seconds or so for it to start up again
Try a hard restart of the Chromebook:
Hold down the refresh button and power button at the same time for 10 seconds
After 10 seconds, let go of both buttons
Press the power button to turn on the Chromebook
If the hard restart does not work, try again but hold down the buttons for 30 seconds:
Hold down the refresh button and power button at the same time for 30 seconds
After 30 seconds, let go of both buttons
Press the power button to turn on the Chromebook