The formula of the hydrogen ion is often written as what?

In the millikan oil drop experiment they determined that every drop had a charge which was a while number multiple of -1.60x10^-19. if a drop has a total charge of -9.60x10^-19 then how many excess electrons are contained within the drop?

The diagram below shows the different phase transitions that occur in matter. which arrow represents the transition in which dew is formed?

Which element has the lowest electronegativity? calcium(ca) gallium(ga) selenium(se) bromine(br)