We have seen that the behavior of gases can be described by 4 variablestemperature, pressure, volume and number of moles. Let's study the link between thepressure and the number of moles in a situation where the other two variablesremain constant. a) Using a few sentences, equations or diagrams, clearly explainsthe relationship between pressure and the number of moles. Your answer must include the notion ofcollisions to justify a pressure change. To help you answer, think ofcomplete the following sentence: "If the number of moles increases the pressure" (directly proportional or inversely proportional?) and thenjustify your choice.b) A balloon contains 4.0 moles of gas at a pressure of 1.6atm. you leave gasout of the balloon to end up with only 3.0 moles of gas. What's the newspressure inside the balloon, assuming that the volume and temperature have notnot changed. c) You need the identity of the gas to answer the question correctlyformer. True or false? No substantiation required.

Respuesta :

Answer and Explanation

(a) At constant temperature and volume the pressure of a gas is directly proportional to the number of moles of gas.

P = n (RT/V) where P is the pressure, n is the number of moles, R is the gas constant, T is the temperature and V is the volume

So when the pressure in increased, the volume will be decreased, meaning there will be less space in the container, this will lead to more collisions inside a container, meaning, the number of moles will be increased.

[tex]\frac{P_1}{n_1}\text{ = }\frac{P_2}{n_2}[/tex]

(b) Given: initial number of moles (n1) = 4.0 moles

initial pressure (P1) = 1.6 atm

Final number of moles (n2) = 3.0 moles

Required: Final Pressure (P2)

solution

P1/n1 = P2/n2

P2 = P1*n2/n1

P2 = 1.6 atm*3.0 moles/4.0 moles

P2 = 1.2 atm