<h3><u>Condensation of gases into liquids by kinetic molecular theory:</u></h3>
The "kinetic molecular theory" explains the states of matter based on the matter composed of very tiny little particles that are constantly in motion. The theory also explains the observable properties and behaviors of solids, liquids, and gases.
Condensation of particles of a real gas to form liquid is due to the attractive forces present in between them. During the condensation process, gas molecules slows down and come together to form a liquid. And also during the transfer of energy to something cooler, the process slows down and they attract the bond to become liquid. Each particle motion is completely independent. The kinetic energy of gas particles is dependent on the temperature of the gas.
<em>Answer :</em> 72.05 g/mol
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<em>Explanation : </em>
Let's </span>assume that the given gas is an ideal gas. Then we can use ideal gas equation,<span>
PV = nRT<span>
</span>
Where,
P = Pressure of the gas (Pa)
V = volume of the gas (m³)
n = number of moles (mol)
R = Universal gas constant (8.314 J mol</span>⁻¹ K⁻¹)<span>
T = temperature in Kelvin (K)
<span>
The given data for the gas </span></span>is,<span>
P = 777 torr = 103591 Pa
V = </span>125 mL = 125 x 10⁻⁶ m³<span>
T = (</span>126 + 273<span>) = 399 K
R = 8.314 J mol</span>⁻¹ K⁻¹<span>
n = ?
By applying the formula,
103591 Pa x </span>125 x 10⁻⁶ m³ = n x 8.314 J mol⁻¹ K⁻¹ x 399 K<span>
n = 3.90 x 10</span>⁻³<span> mol
</span>Moles (mol) = mass (g) /
molar mass (g/mol)<span>
Mass of the gas = </span><span>0.281 g
</span>Moles of the gas = 3.90 x 10⁻³ mol
<span>Hence,
molar mass of the gas = mass / moles
= 0.281 g / </span>3.90 x 10⁻³ mol
<span> = 72.05 g/mol
</span>
Initial buret reading means the volume of acid taken in the buret and final reading means the remaining volume of acid after experiment