Under identical conditions, separate samples of o2 and an unknown gas were allowed to effuse through identical membranes simultaneously. after a certain amount of time, it was found that 8.44 ml of o2 had passed through the membrane, but only 3.95 ml of of the unknown gas had passed through. what is the molar mass of the unknown gas?

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

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

In vapor-liquid equilibrium in a binary mixture, both components are generally present in both phases. how many degrees of freedom are there for such a system? the reaction between nitrogen and hydrogen to form ammonia occurs in the gas phase. how many degrees of freedom are there for this system? steam and coal react at high temperatures to form hydrogen, carbon monoxide, carbon dioxide, and methane. the following reactions have been suggested as being involved in the chemical transformation: