How Does Increasing RMS Speed Affect Gas Temperature?

In summary, in order to find the change in temperature when the rms speed of a gas is increased by 8 percent, we can use the equation \Delta T = 0.08T (where T is the original temperature). If the volume is held constant, the change in temperature can be found using the equation \Delta T = 0.0864T (where T is the original temperature).
  • #1
Nghi
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Homework Statement



The rms speed of a sample of gas is increased by 8 percent.

(a) By how much does the gas's temperature change? (given in %)
(b) By how much does the gas's temperature change, assuming its volume is held constant? (%)

Homework Equations



rms = [tex]\sqrt{3KT/M}[/tex]

The Attempt at a Solution



I have no idea how to solve this. I set the left side of the equation equal to 0.08, and then I got lost from there. -__-
 
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  • #2




Thank you for your question. Let me guide you through the solution step by step.

(a) To find the change in temperature, we first need to understand how the rms speed is related to temperature. The rms speed is directly proportional to the square root of the temperature, as seen in the equation rms = \sqrt{3KT/M}. This means that if we increase the rms speed by 8 percent, the temperature will also increase by 8 percent. This can be written as:

\Delta T = 0.08T

(b) Now, let's assume that the volume is held constant. In this case, the ideal gas law can be used, which states that PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is the temperature. Since the volume is constant, we can rearrange the equation to get:

T = \frac{PV}{nR}

Now, let's substitute this into the equation for rms speed:

rms = \sqrt{3K\frac{PV}{nR}\frac{1}{M}}

To find the change in temperature, we need to find the new rms speed and then solve for T. Since the rms speed has increased by 8 percent, the new rms speed will be 1.08 times the original rms speed.

rms_{new} = 1.08rms_{original}

Substituting this into the equation for rms speed and solving for T, we get:

T_{new} = 1.08^2T_{original}

This means that the temperature will increase by 8.64 percent. We can write this as:

\Delta T = 0.0864T

I hope this helps you understand the solution better. Please let me know if you have any further questions. Good luck with your studies!


 
  • #3


As a scientist, let's break down the problem and approach it step by step.

First, let's define some terms. rms speed refers to the root-mean-square speed, which is a measure of the average speed of particles in a gas. It is calculated using the equation rms = √(3KT/M), where K is the Boltzmann constant, T is the temperature in Kelvin, and M is the molar mass of the gas.

Now, let's address part (a) of the problem. We are given that the rms speed of the gas has increased by 8%, so we can write this as:

rms_new = 1.08 * rms_old

Since the temperature (T) is directly proportional to the rms speed (rms), we can say that the temperature has also increased by 8%. Therefore, the gas's temperature change is 8%.

For part (b), we need to assume that the volume of the gas is held constant. This means that the number of particles (n) and the molar mass (M) are also constant. Using the ideal gas law, PV = nRT, we can rearrange it to get T = PV/nR.

Since the volume (V) and the number of particles (n) are constant, the temperature (T) is directly proportional to the pressure (P). Therefore, if the rms speed increases by 8%, the temperature will also increase by 8%.

In conclusion, the gas's temperature change is 8% for both parts (a) and (b) of the problem.
 

FAQ: How Does Increasing RMS Speed Affect Gas Temperature?

What is RMS?

RMS stands for Root Mean Square, and it is a mathematical term used to describe the average value of a set of numbers. In the context of gas speed, RMS refers to the most probable or average speed of gas particles in a given sample.

How is RMS related to gas speed?

The RMS of gas particles is directly related to their speed. The higher the RMS, the faster the particles are moving. This is because RMS takes into account the speed of all particles in a sample, rather than just the average speed.

What factors affect the RMS of gas particles?

The RMS of gas particles is affected by temperature, pressure, and the type of gas. Higher temperatures and pressures generally result in higher RMS values, while different types of gases have different RMS values at the same temperature and pressure.

Why is understanding RMS important in studying gases?

RMS is an important concept in the study of gases because it helps us understand the behavior of gas particles. It allows us to predict the average speed of particles and how they will interact with each other and their surroundings. This knowledge is crucial in many fields, including chemistry, physics, and engineering.

How is gas speed measured?

Gas speed can be measured in a variety of ways, including using specialized equipment such as gas flow meters or anemometers. It can also be calculated by measuring the distance traveled by a gas particle over a period of time, or by using the ideal gas law to estimate the speed of particles based on temperature, pressure, and volume.

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