because there are the same number of protons and electrons, therefore for a regular O, you are supposed to have only 8 protons, but it is charged, thus, whatever the charge is will be taken into consideration into how much the proton and electron doe it have. Thus, for this case, it has 10, because the charge is negative and you have 8 electron plus 2 = 10.
Science is a continuous profession of study because new ideas are produced based on new evidence. Also, there are different topics of science such as climate change or new cures to different diseases.
