An effusion apparatus allows a certain quantity of butane, C4H10, to escape in 136 seconds. 106 seconds are required for the same number of moles of an unknown gas to be released. What is the molar mass of the second gas?

16. in a reaction that has reached equilibrium, a. the forward and reverse reactions are occurring at the same rate. b. the reactants and products are in equal concentrations. c. the forward reaction has gone further than the reverse reaction. d. there are equal numbers of atoms on both sides of the equation. e. a, b, and d are correct.