What would be the charge of an ion with 9 protons, 10 neutrons, 10 electrons

negative

Explanation:

Any atom whose number electrons are more than the number of protons in it will have a negative charge. Since in this case the electrons are 10 and protons are 9 the 9+ charge protons and 9- charge electrons cancel each other giving a final charge of negative.

i just learnt this recently but i need to look through my notes again