The average atomic mass recorded on the periodic table for cobalt is 58.933 u. this indicates that the most abundant isotope of cobalt is
a.) cobalt-57
b.) cobalt-58
c.) cobalt-59
d.) cobalt-60

Which of the following did jj thompson discover about atoms? a)an atom has an internal structure. b) atoms are tiny indivisible particles. c)electrons orbit the nucleus of an atom. d) the nucleus of an atom contains protons and neutrons.

What is the work done by the electric force to move a 1 c charge from a to b?

How does a sample of helium at 15 degree celsius compare to a sample of helium at 215 k? a) the helium at 15 degrees celsius has a higher average kinetic energy that the sample at 215 k. b) the helium at 15 degrees celsius has lower nuclear energy that the sample at 215 k. c) the helium at 15 degrees celsius has slower- moving atoms that the sample at 215 k. d) the helium at 15 degrees celsius has smaller atoms than the sample at 215 k.