Show that the units of kinetic energy (from 1/2mv^2) and of gravitational potential energy (from mgh) are the same.

Write the symbol for every chemical element that has atomic number greater than 3 and atomic mass less than 12.0 u.

Tin has ten stable isotopes. the heaviest, 124sn, makes up 5.80% of naturally occuring tin atoms. how many atoms of 124sn are present in 82.0 g of naturally occurring tin? what is the total mass of the 124sn atoms in this sample?

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)