Asample of an unknown gas effuses in 12.1 min. an equal volume of h2 in the same apparatus under the same conditions effuses in 2.42 min. what is the molar mass of the unknown gas?

MW H2 = 2

MW 2 = ?

rate 1 = 1/12.1

rate 2 = 2.42

aopply graham law

Rate1/rate2 = sqrt(MW2/MW1)

(12.1/2.42)^2 = MW2/2

MW = 2(12.1/2.42)^2 = 50 g/mol

Therefore, the molar mass of the unknown gas is 50 g/mol

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.