An equimolar mixture of H2 and D2 effuses through an orifice (small hole) at a certain temperature,
Calculate the composition (in mole fractions) of the
gases that pass through the orifice. The molar mass
of D, is 2.014 g/mol. Answers are .586 and .414 but I need help getting there.

Asample of air with a volume of 2.20m3 at a pressure of 105 kpa and a temperature of 30c is cooled to 10c and the pressure is reduced to 75.0 kpa. what is the new volume? 6.9 1.34 2.56 43.0 2.88

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.