A balloon is filled with helium gas has a volume of 1.0 L at a pressure of 1.0 atm. The balloon is released and reaches an altitude where the pressure is now 0.4 atm. What is the
new volume of the balloon at this altitude assuming the air temperature has not changed?

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

The atoms of a solid aluminum can are close together, vibrating in a rigid structure. if the can is warmed up on a hot plate, what happens to the atoms?

What volume would 2.25 moles of ne has occupy at stp?