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 60.0 Liters in size. Will the balloon make it to the necessary height without bursting? The temperature at ground level is 20 C. The pressure is 755 mm hg. The volume of the balloon prior to release is 44.8 Liters. It is filled with helium which is lighter than air. For both calculation you will be using PV =nRT show all work for any credit. 1. What amount in grams of helium is in the balloon? Hint remember n = moles.
A:pV = nRT
(755 mm Hg)(44.8 L) = n(62.36 mm Hg-L/mol-K)(20 + 273K)
n = 1.85 mol
How does: n(62.36 mm Hg-L/mol-K)(20 + 273K)
n = 1.85 mol
When I do the math I come up with something different. What am I doing wrong?
Molecules A and B react to produce molecule AB. If 60 mLs of 0.025 M A
is added to 18 mLs of 0.175 M
B, then how many moles of unreacted A or B will be left over? How many moles of AB will be produced?
I don't understand what you're having trouble with. Will you please clarify?
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I don't understand what 62.36 mm hg is, and if you divide that amount by 293k (20 + 273), it doesn't come out to 1.85 mol.
To find the amount of helium in grams, you need to use the ideal gas law equation, PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature in Kelvin.
Given information:
- Pressure at ground level = 755 mm Hg
- Volume of balloon prior to release = 44.8 Liters
- Temperature at ground level = 20°C
First, convert the temperature from Celsius to Kelvin by adding 273.
20°C + 273 = 293K
Now, substitute the values into the equation:
(755 mm Hg)(44.8 L) = n(62.36 mm Hg·L/mol·K)(293K)
To solve for n (the number of moles), divide both sides of the equation by (62.36 mm Hg·L/mol·K)(293K):
(n)(62.36 mm Hg·L/mol·K)(293K) = (755 mm Hg)(44.8 L) / (62.36 mm Hg·L/mol·K)(293K)
Simplifying and solving this equation will give you the value for n (moles). In this case, n is calculated to be 1.85 mol.
Therefore, the amount of helium in grams can be determined by multiplying the number of moles (n) by the molar mass of helium (4 grams/mol).
If you're getting a different answer, check your calculations and ensure that you're using the correct values for pressure, volume, temperature, and the gas constant.