The cathode ray tube experiment determined: A) The mass-to-charge ratio of the proton
B) The existence of electrons
C) The mass-to-charge ratio of the neutron
D) The charge of the electron
E) The mass of the electron

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.