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Posted by **T** on Saturday, December 15, 2012 at 2:49am.

- Chemistry (balloon) -
**.**, Saturday, December 15, 2012 at 3:41amA latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.7 kg m-3. Under these conditions the total surface area of the balloon is 0.52 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of helium effusion (in g/hr) from the balloon.

- Chemistry (balloon) -
**Antonio**, Saturday, December 15, 2012 at 6:23amThis is a question from the second midterm of 3.091x by edx. Stop cheating, it's silly and pointless.

- Chemistry (balloon) -
**Anonymous**, Saturday, December 15, 2012 at 2:31pm42.8

- Chemistry (balloon) -
**qpt**, Saturday, December 15, 2012 at 4:50pmHow did you get it? could you show the data in the formula? Thank you

- Chemistry (balloon) -
**chelo**, Saturday, December 15, 2012 at 5:51pmTHE FORMULA

- Chemistry (balloon) -
**anono**, Saturday, December 15, 2012 at 10:41pmA latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.94 kg m-3. Under these conditions the total surface area of the balloon is 0.53 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of helium effusion (in g/hr) from the balloon.

- Chemistry (balloon) -
**Stud**, Saturday, December 15, 2012 at 11:19pmFicks Law

M= -D(Δρ/Δx)A,

where

M = m/t = mass flux [kg/s],

D= 4.910 ⁻⁹ m ²/s is the diffusion coefficient (diffusivity) [m²/s],

Δρ/Δx is the gradient of density [kg/m⁴],

A is the area [m²].

M= - 4.910⁻⁹(0 - 0.35)/3.09110⁻⁴)0.88 =

4.910⁻⁹0.350.88/3.09110⁻⁴=

=4.8810⁻⁶ kg/s= 17.58 g/hr - Chemistry (balloon) -
**nenita**, Sunday, December 16, 2012 at 1:06pmthanks stud

- Chemistry (balloon) -
**me**, Sunday, December 16, 2012 at 5:50pmHOW CAN I SOLVE WITH THESE NUMBERS?

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.82 kg m-3. Under these conditions the total surface area of the balloon is 0.5 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of helium effusion (in g/hr) from the balloon. - Chemistry (balloon) -
**Anonymous**, Sunday, December 16, 2012 at 11:05pmhow do you approach and solve it?