Solve the following problems on ideal gas equation. Practice makes perfect. 1. A toy balloon filled Analyze
with air has an
internal pressure of
1.25 atm and a
Calculate
volume of 2.50 L.
How many moles of
gas does the balloon
Answers: 1., 0.130 mol, 2.,0,012 mol, 3., 26 220 torr, 4., 1.07 atm
hold? (Assume T =
285 K)
Final Answer

2. A certain quantity of Analyze:
argon gas is under 16
torr pressure at 253K
in a 12 L vessel. How Calculate
many moles of argon
is present?
Final Answer

3. If 11.00 moles of HC1 Analyze:
gas occupies 15.00 L
at 300.0 °C, what is
its pressure in tort? Calculate
Final Answer
Analyze

4. What would be the
pressure of 6.40 g
oxygen gas in a

0.012mol

Explanation:

1.

Given parameters:

Pressure in the balloon  = 1.25atm

Volume of the balloon  = 2.5L

Unknown:

Number of moles  = ?

Solution:

We are going to used the combined gas law to solve this problem.

  PV = nRT

P is the pressure

V is the volume

n is the number of moles

R is the gas constant  = 0.082atmdm³mol⁻¹K⁻¹

 Insert the parameters and solve;

    1.25 x 2.5  = n x 0.082 x 285

       n  = 0.13mol

The number of moles is 0.13mol

2.

Given parameters:

Pressure  = 16torr;

   to atm is ;

                 760torr  = 1atm

                  16torr =   = 0.02atm

Volume = 12L

Temperature  = 253K

Using the ideal gas law;

        PV  = nRT

       0.02x12  = n x 0.082 x 253

            n = 0.012mol

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.