At STP, a container has 1 mole of Ar, 2 moles of CO2 , 3 moles of O2 and 4 moles of N2 without changing the total pressure if one mole of O2 is removed, the partial pressure of O2

Question

At STP, a container has 1 mole of Ar, 2 moles of CO2 , 3 moles of O2 and 4 moles of N2 without changing the total pressure if one mole of O2 is removed, the partial pressure of O2 (A) is changed by about 26% (B) is halved (C) is unchanged (D) changes by 30%

Tardigrade Admin · Accepted Answer

In the first case, nA r=1,nC O2=2,nO2=3,nNA=4 So total number of moles =1+2+3+4=10 If P in the total pressure, PO2=(3 P/10) In the second case, nO2=2,nt o t a l=9 As P remains the same, PO2=(2 P/9) So decrease in partial pressure of O2 =(3 P/10)-(2 P/9)=(7 P/90) So % decrease in partial pressure of O2 =((7 P/90)/(3 P)10)× 100=(700/27)=26 %

Q. At STP, a container has 1 mole of Ar, 2 moles of CO2​ , 3 moles of O2​ and 4 moles of N2​ without changing the total pressure if one mole of O2​ is removed, the partial pressure of O2​

is changed by about 26%

is halved

is unchanged

changes by 30%

Q. At STP, a container has 1 mole of Ar, 2 moles of $C O_{2}$ , 3 moles of $O_{2}$ and 4 moles of $N_{2}$ without changing the total pressure if one mole of $O_{2}$ is removed, the partial pressure of $O_{2}$