Helium effusion rate

Hydrogen chloride effuses through a hole (under prescribed conditions of temperature and pressure) at the rate of 2 70 ml/mm At what velocity will helium effuse through the same hole under the same conditions7... 

For example, how much faster does helium effuse than methane The molar mass of helium and methane are 4 g/mol and 16 g/mol, respectively. If we insert these values into Graham s law, we find helium effuses at twice the rate of methane. 

Calculate the ratio of effusion rates of helium (He) and neon (Ne) gases from the same container and at the same temperature and pressure. 

Problem Calculate the ratio of the effusion rates of helium and methane (CH4). 

An unknown gas effuses through an opening at a rate one-fifth as fast as that of helium gas... 

B—Lighter gases effuse faster. The only gas among the choices that is lighter than methane is helium. To calculate the molar mass, you would begin with the molar mass of methane and divide by the rate difference squared ... 

The molar masses of each gas are He = 4 g mol-1, Oz = 32 g mol-1, and COz = 44 g mol-1. Therefore, He will have the greatest rate of effusion, followed by oxygen, and finally C02. This means that helium will have the lowest partial pressure, followed by Oz, and finally C02, which will have the highest partial pressure. 

A sample of helium gas is collected in a container with a tiny hole in it. The helium gas (M = 4 grams) effuses at a rate of 0.2 moles per minute. If a sample of methane gas (M 16 grams) is allowed to effuse under the same conditions, the rate of CH4 effusion will be... 

The correct answer is (A). There is a quick way to solve this and also a long way. The quick way is to remember that Graham s law states that the rate of effusion is inversely proportional to the square root of the molar mass. You can see pretty quickly that the molar mass of methane is 4 times that of helium. The square root of 4 is 2, meaning that helium will diffuse two times faster than methane. The longer way is to actually set up the equation — = and solve for r2. 

D) Wrong Graham s law of effusion states that the rates of effusion are inversely related to the square root of the molar mass. This means that smaller particles will effuse more quickly than larger particles. All three balloons will get smaller at different rates, which means they will be different sizes on the next day (hydrogen will be smallest, followed by helium, and then sulfur hexafluoride). 

FIGURE 9.19 A small hole in the box permits molecules to effuse out into a vacuum. The less massive particles (here, helium atoms, red) effuse at greater rates than the more massive oxygen molecules (purple) because their speeds are greater on the average. 

Calculate the rate of effusion of helium from a porous cup under the same conditions that CH4 effuses at a rate of... 

If it takes 3.52 s for 10.0 mL of helium to effuse through a hole in a containCT at a particular temperature and pressure, how long would it take for 10.0 mL of oxygen, O2, to effuse from the same container at the same tempauture and pressure (Note that the rate of effusion can be given in terns of volume of gas effused per second.)... 

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