Suppose the volume of the syringe is 45.8 cc. You measure the pressure as 1.49 a

Question

Suppose the volume of the syringe is 45.8 cc. You measure the pressure as 1.49 atm, and the temperature as 19.4oC. Assume: the diameter of the plunger on the syringe is 1.34 cm.

a)Find
- n, the number of moles of gas in the syringe: moles
- N, the number of molecules of gas in the syringe: molecules
- Use the molear mass of air given to calculate the mass of air in the syringe: kg

b)Supose you push down the syringe so the volume is now 40.5 cc, with the temperature remaining unchanged. Find:
- the new pressure inside the syringe. atm
- the force exerted by the gas on the plunger of the syringe: N

Explanation / Answer

b) As temparature is constant this is isothermal

so, P1V1=P2V2

P2 = P1V1/V2

= (1.49x45.8)/40.5

= 1.6849 atm

F = P2*A

= 1.6849*(1.03x10^5) N/m2 * pi*(d/2)^2

= 1.6849*(1.03x10^5) N/m2 * pi*(0.67x10^-2)^2 m2

= 24.48 N

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.