10. In which of the following is the symbol for the ion and the total number of electrons it contains given correctly? A Al3+ has 16 electrons B S2- has 2 electrons C Br1- has 34 electrons D Ca2+ has 18 electrons
9. Which total mass is the smallest? A The mass of 2 electrons B The mass of 2 neutrons C The mass of 1 electron plus the mass of 1 proton D The mass of 1 neutron plus the mass of 1 electron
8. After measuring the ratio of the charge of a cathode ray particle to its mass, Thomson concluded that the particles A Had no mass B Had a very small mass C Had a very large mass D Carried a positive charge