How many atoms of Ar gas are present in a 340 mL container at 55 °C and 720 mmHg? A)0.012 Ar atoms B)7.2 x 10²¹ Ar atoms C)4.3 x 10²² Ar atoms D)2.9 x 10²³ Ar atoms E)1.7 x 10²⁴ Ar atoms

Question

Quizplus · Accepted Answer

We can use the ideal gas law to determine the number of moles of Ar gas present in the container:

PV = nRT

where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature in Kelvin.

First, we need to convert the temperature from Celsius to Kelvin:

T = 55°C + 273.15 = 328.15 K

Then, we convert the volume from mL to L:

V = 340 mL = 0.34 L

Next, we can substitute the given values into the ideal gas law:

(720 mmHg)(0.34 L) = n(0.0821 L atm/mol K)(328.15 K)

Solving for n, we get:

n = 0.0152 moles of Ar

Finally, we can use Avogadro's number to convert from moles to atoms:

(0.0152 moles)(6.022 x 10^23 atoms/mol) = 9.16 x 10^21 Ar atoms

Therefore, the answer is C) 4.3 x 10^22 Ar atoms.

How Many Atoms of Ar Gas Are Present in a 340