Question

A balloon is filled with 5000.00 milligrams of helium gas at STP. What is the volume of the

balloon? (Use the ideal gas law and gfm for a start. (Molar volume of a gas))

Answer 1

Assuming that helium behaves as an ideal gas, we know that a mole of ideal gas occupies 22.4 litres at STP. The atomic weight of helium is 4 g/mol, so 6 g is 1.5 moles. The volume occupied at STP, therefore, is 22.4 x 1.5 = 33.6 litres.

Step-by-step explanation:

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Answer 2

The answer to your question is V = 30.03 L

Step-by-step explanation:

Data

mass of Helium = 5000 mg

Volume = ?

Temperature = 20°C

Pressure = 1 atm

constant of ideal gas = 0.082 atmL/mol°K

Process

1.- Calculate the moles of Helium

Atomic mass = 4 g

5000 mg = 5 g

4g --------------- 1 mol

5g ---------------- x

x = (5 x 1)/4

x = 5/4 moles

2.- Convert temperature to °K

Temperature = 20 + 273 = 293°K

3.- Use the ideal gas law to find the volume

PV = nRT

-Solve for V

V = nRT / P

-Substitution

V = (5/4)(0.082)(293) / 1

-Simplification

V = 30.03 L