On the top of Mount Everest, the total atmospheric pressure is reduced to 33.73 kPa (about one-third of its value at sea level).
Assume that the fraction of the atmosphere that is made up of oxygen is the same at all elevations.
If the partial pressure of oxygen at sea level is 21 kPa, what is the partial pressure of oxygen on the top of Mount Everest?
A 12.73 kpa
B 11.2 kpa
C 54.73 kpa
D 7.0 kpa

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explanation:

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2

answer7,570,82356 cubic centimeters;