Calculate ,Volume, in L, of 3.4 mole sample of hydrogen gas at a pressure of 2.1 ATM at 23 °C. Please show step by step so I can comprehend all steps

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

A50.0g sample of liquid water at 0.0 c ends up as ice at -20.0 c. how much energy is involved in this change?

An animal cell loses the ability to convert energy stored in food to energy that the cell can use. which of the cell's organelles has stopped working? a.the mitochondria b.the nucleus c.the vacuoles d.the endoplasmic reticulum