Chemistry
posted by Anonymous .
You are completing tests using a weather balloon and want to check the temperature at 3000 meters into the air. You check if the balloon will not burst before it gets to that altitude. You will need to perform a few calculations. The manufacturer of the balloon guarantees it up to 47.0 Liters in size. Will the balloon make it to the mentioned altitude without bursting? The temperature at ground level is 20 C. The pressure is 765 mmHg. The volume of the balloon prior to release is 30.0 Liters. It is filled with helium. Use PV = nRT for both the calculations below.
1. Calculate the number of grams of helium in the balloon.
2. Find if the balloon can reach 3000 meters without bursting. The temperature and pressure at 3000 meters was measured at Temp = 6.0 C, Pressure = .565 atm
I found the number of grams to be 5.0251. However, I don't see how the grams can be used to answer the second question. Is there something I'm missing?

n = 1.25 and 5.025 g He is correct for #1.
#2.
PV = nRT
P is 0.565 atm
T is 6.0. Convert to kelvin first.
n from above is 1.25
R you know
Solve for V and compare it with the manufaturer's value of not bursting up to 47.0 L 
So the grams are not needed to answer the second question?

Yes grams are and no grams are not. You calculated grams in part 1 by using PV = nRT, then since n = grams/molar mass, you substituted molar mass of 4 for He and calculated grams.
For part 2, you used PV = nRT again and if you wanted to use grams, then mols = n = grams/molar mass (n = 5.02/4) and you substitute the n value for mols BUT since you already had mols of 1.25 from part a, why go through the extra step.
Respond to this Question
Similar Questions

chemistry
A weather balloon is inflated to a volume of 27.0 at a pressure of 730 and a temperature of 31.3. The balloon rises in the atmosphere to an altitude, where the pressure is 365 and the temperature is 14.6. Assuming the balloon can … 
Chemistry
Bill and Bob have been testing a new aluminised PET (Polyethylene Terephthalate) film and they now use the material to make helium filled balloons. Bill’s balloon is less inflated than Bob’s, and the latter jokes about it. However, … 
Chemistry
Bill and Bob have been testing a new aluminised PET (Polyethylene Terephthalate) film and they now use the material to make helium filled balloons. Bill’s balloon is less inflated than Bob’s, and the latter jokes about it. However, … 
chemistry
A very flexible heliumfilled balloon is released from the ground into the air at 20 degree C. The initial volume of the balloon is 5.00 L, and the pressure is 760 mmHg. The balloon ascends to an altitude of 20km, where the pressure … 
Physics
A hot air balloon of radius 12 meters has been heated so that the air inside has a density of 1.05 kg/m^3. What can the total load of the balloon be (mass of balloon itself plus cargo) if you need the balloon to accelerate into the … 
Chemistry
A weather balloon is inflated to a volume of 25.6L at a pressure of 736mmHg and a temperature of 31.9∘C. The balloon rises in the atmosphere to an altitude, where the pressure is 365mmHg and the temperature is 15.6∘C. … 
Chemistry
I found this on the internet and I need an explanation. Q: You want to make sure a large weather balloon does not burst and wish to check the temperature at 3000 meters altitude. The balloon manufacture guarantees the balloon up to … 
Physics
A weather balloon is released at an altitude of 500m. The force of gravity on the balloon is 21.1n. The lift force provided by the atmosphere is 18.7n. Which of the following is true about the balloon? 
Chemistry
A weather balloon is inflated to a volume of 26.2 L at a pressure of 755 mmHg and a temperature of 32.5 ∘C. The balloon rises in the atmosphere to an altitude where the pressure is 360. mmHg and the temperature is 13.5 ∘C. … 
Chemistry
A weather balloon is inflated to a volume of 29.9 L at a pressure of 755 mmHg and a temperature of 33.0 ∘C. The balloon rises in the atmosphere to an altitude where the pressure is 385 mmHg and the temperature is 16.2 ∘C. …