A gas in a container has a pressure of 0.77 atm, volume of 65,5 L and a temperature of 235 K. If the gas is helium, what mass of helium is in the container?
A) 2.61 g
B) 10.5 g
C) 0.625 g
D) 0.859 g

B) 10.5

Explanation:

PV= NRT     -> N=PV/RT

N= mols .     P= pressure . V= volume in Liters    T= temp in Kelvin (Celsius degree = 273.15) .  R= Gas constant (.0821 for atm)

N=(.77 x 65.5)/(.0821x235) = 2.614 mols of Helium

Mols x Molecular weight = weight in grams

2.614x4.003(Molecular weight ot He) = 10.46 round to 10.5  

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.

the answers would be

the first one and the second one