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?

Read these sentences from the text. near the equator, the tropics receive the most rain on a consistent basis. as a result, the fresh water falling into the ocean decrease the salinity of the surface water in that region. [. .] . . as the salt content of sea water increases, so does its density. what can you infer about how rain affects the density of surface water near the equator?

Avariable that is not being directly tested during an experiment should be changed varied experimented controlled

All forces cause motion? true or false