J. J. Thompson discovered the first subatomic particle, , by deflecting a "cathode ray" beam with an electric field. Robert Millikan later determined that
particle's charge in his "oil drop" experiments.
A) the proton
B) the nucleus
C) the neutron
D) the electron

13. a covalent bond between two atoms is likely to be polar if: a. one of the atoms is much more electronegative than the other. b. the two atoms are equally electronegative. c. the two atoms are of the same element. d. the bond is part of a tetrahedrally shaped molecule. e. one atom is an anion.

Which description best characterizes the motion of particles in a solid?

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)