Can R change?
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Can R change?
Are there any conditions where we would need to adjust the value of R in order to provide accurate calculations?
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Re: Can R change?
The R in PV=nRT can have these values depending on the units:
1) 8.314 J/mol·K
for ideal gas laws, if the pressure is measured in Pascal and volume measured in cubic meters, then we use 1).
2) 0.0821 atm-litre/mol*kelvin
for ideal gas laws, if the pressure is measured in atm and volume measured in liter, then we use 2).
1) 8.314 J/mol·K
for ideal gas laws, if the pressure is measured in Pascal and volume measured in cubic meters, then we use 1).
2) 0.0821 atm-litre/mol*kelvin
for ideal gas laws, if the pressure is measured in atm and volume measured in liter, then we use 2).
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Re: Can R change?
R is a constant so the true value of it does not change but the value you would insert into the equation will depending on the units used.
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Re: Can R change?
The value of R would only need to be changed based on the units being used in the calculation, but since it is a constant, each value corresponding with the different units should be equivalent.
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Re: Can R change?
Hi Ethan!
R itself is a constant and does not change, but it is often seen with different units and therefore different numerical values depending on what units it is in.
R itself is a constant and does not change, but it is often seen with different units and therefore different numerical values depending on what units it is in.
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Re: Can R change?
Hi Ethan, there wouldn't be a condition where you'd need to adjust the value of R for calculations unless you are working with different units. Since R is a constant, its value is not dependent on any other factors. Hope this helps!
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Re: Can R change?
The equation sheet has 4 different values for R due to unit differences. R is a different value depending on if it is measured in joules, atmospheres, bar, or torr. The value of R itself is constant though, differing only due to unit differences.
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Re: Can R change?
R is a constant but it differs depending on the units given in the equation/problem
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Re: Can R change?
In the ideal gas equation, the partial pressure of a particular gas (p) multiplied by the volume that gas is occupying (v) equals the 3 constants that DO NOT change - moles of that gas (n) multiplied by temperature in Kelvin (T) multiplied by the gas constant (R). This R can have different units - the most common one being J/mK - but it will not change because it is a constant, making it a constant value.
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Re: Can R change?
R is a constant and will not change, however, there are two different values that you will use depending on the units. It'll be R=8.3145 J/molK or 0.0821 atmL/molK.
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Re: Can R change?
R is an experimental constant therefore it would only change depending on what units you are using
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Re: Can R change?
R is a constant, not a variable, so it will only change with respect to the units you are using.
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Re: Can R change?
no! R is a constant, and while it can be different depending on what units are being used, it is the same value of 0.0821 atm*L/mol*K
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Re: Can R change?
Because R is a constant, the actual value of it does not change. However, the units might, in which case, the number will reflect the change in the units. When using Joules, the value of R is approximately 8.314 J/(mol•K). When using atm•liters, the value of R is approximately 0.08206 atm•liter/(mol•K).
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Re: Can R change?
R is a constant used in the ideal gas law equation. It will always stay the same, unless you use different units.
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Re: Can R change?
R is the gas constant (8.206 x 10^-2 L·atm·K^-1 ·mol^-1), so its value will not change.
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Re: Can R change?
Hi, R itself is constant, so the overall value of it will not change. However, depending on the units you are using, the numerical value will be different. So, the amount of R will remain the same, the difference is only in the units used to measure said amount.
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Re: Can R change?
Since R is a constant, the value does not change but depending on what units you are provided, you might have to be convert numbers to match the correct units of R which is L atm / mol K
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Re: Can R change?
No, because it is a constant but that does not mean that you can't convert it so it has different units, but still maintains the same value.
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Re: Can R change?
R doesn't "change" because it is a constant, but it can take on different numbers depending on which units you use to derive the R value.
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Re: Can R change?
R remains the same constant (2 values) but must be used depending on the values needed for the equation
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Re: Can R change?
As long as the units involved in the R constant do not change from the standard, then R will not change.
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Re: Can R change?
R is a constant and does not change. R is a different value depending on the units used.
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Re: Can R change?
Since R is a constant, the actual value does not technically change, but the numeric value could change depending on which units are used
Re: Can R change?
R is constant and does not change. The numerical value used for R can differ depending on the units but it is the same.
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Re: Can R change?
Hi! R is a constant, so it technically doesn't change. However, the R value can be different depending on which units you're using in the PV=nRT equation, but ultimately they're all the same value after being converted to the same units.
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Re: Can R change?
R is a constant and has different values that correspond to the units. These values would be given to you rather than having to be calculated through conversions.
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Re: Can R change?
R is a constant value so it does not change. But, there are different ways of going about expressing the value of R due to using different units.
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Re: Can R change?
Hello,
R does not change since it is a constant! However, it may change if the units are altered. R is also known as the molar gas constant. I hope this helped!
R does not change since it is a constant! However, it may change if the units are altered. R is also known as the molar gas constant. I hope this helped!
Re: Can R change?
The actual value of R will not change, but you may have to write it a different way depending on what units are being used!
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Re: Can R change?
R is a constant, but there can be different values for it depending on which units you are using.
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Re: Can R change?
No because R itself is a constant and does not change, we can, however, see different units representing it.
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Re: Can R change?
R cannot change, as it is a predetermined constant, much like Planck's constant or c, the speed of light. However, it may be represented by different numbers in different situations, depending on the units being used to measure it.
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Re: Can R change?
R is a constant, so its value does not change. It can be expressed as different numbers based on the units involved, so be careful to use the correct one based on the pressure units!
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Re: Can R change?
R cannot change as it is a constant. However, the value of it can change depending on which units you are using.
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Re: Can R change?
No, R does not change. It is a constant and doesn't change when other variables change.
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Re: Can R change?
The value of R would only need to be changed based on the units being used in the calculation
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Re: Can R change?
R is the gas constant, so it cannot change. Only the units can (which means you can convert the number).
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Re: Can R change?
R is constant and cannot be changed. However, it depends on which units are being used.
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Re: Can R change?
Unless you need to switch units between J/(K*mol) to (L*atm)/(K*mol), then R should stay the same. Both of these values are on the constants and equations sheets, so just make sure you're aware of what units the question is asking for.
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Re: Can R change?
Since R is a constant, it won't change. But, there are different R values based on the different units. You would need to select the R value that has the same units as the other values in the problem.
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Re: Can R change?
R is a constant meaning its true value doesn't change, however, it could change if you are using different units
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Re: Can R change?
R is a constant, so it doesn't change. However, there are different values of R depending on the units.
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Re: Can R change?
The true value of R will remain the same since R is a constant, but its numerical value will vary depending on the units which are used.
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Re: Can R change?
Hi! R is actually a constant, so the value itself doesn't change, however, it can be a little different depending on the units you're using! I hope that helped!
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Re: Can R change?
Since R is a constant, its value will not change unless you change the units of R, which are either J/(K*mol) or (L*atm)/(K*mol), because the value of R is different for these 2 units.
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Re: Can R change?
R being a constant means that it does not change, but its units may be expressed differently through conversions. Typically, we would use R = 8.314 J/K*mol.
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Re: Can R change?
R changing only happens with unit changing but it is a constant. R = 8.314 J/K*mol but that would need to be converted based on units.
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Re: Can R change?
Hi!
R is a constant in the ideal gas equation, but depending on the units used in the question, this constant can be converted. So, R could be 8.314 J/Kmol or 0.0821 Latm/Kmol.
I hope this helps!
R is a constant in the ideal gas equation, but depending on the units used in the question, this constant can be converted. So, R could be 8.314 J/Kmol or 0.0821 Latm/Kmol.
I hope this helps!
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Re: Can R change?
Hi Ethan!
R is dependent on the units you have available to you, so depending on what equation you are using you'll use a different value for R with different units.
R is dependent on the units you have available to you, so depending on what equation you are using you'll use a different value for R with different units.
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Re: Can R change?
The value of R itself doesn't change because it is a constant, however there are different R values to use depending on the units you have in your equation.
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Re: Can R change?
No, R cannot change because it is a constant. However, it is important to recognize that there are different R values depending on the units in the equation.
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Re: Can R change?
No, R cannot change because it is a constant. However, it is important to recognize that there are different R values depending on the units in the equation.
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Re: Can R change?
Since R is a constant, it wouldn't change like other numbers would at different temperatures or conditions. However, just like other constants, there are different versions you can use depending on the units that you are working with.
R= 8.314 Joule/mol*Kelvin(In SI unit)
Or
R= 0.0821 atm-litre/mol*kelvin
R= 8.314 Joule/mol*Kelvin(In SI unit)
Or
R= 0.0821 atm-litre/mol*kelvin
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Re: Can R change?
R will not change because it is a constant. However, there may be different values because of different units.
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Re: Can R change?
Hi Ethan! R is simply a constant that is used in these equations that allow for stoichiometry in various different equations to cancel certain units of measurement out, and therefore we simply use the value of the constant that allows for this to work.
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Re: Can R change?
Depending on the units of the values given in the problem, you may have to use a different value of R
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Re: Can R change?
R is a constant but there are two R constants so you can choose which one best fits what you are solving for.
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Re: Can R change?
R is a constant, meaning that it does not change. Rather, there are different values for R depending on the units that are used. For instance, in the table below, it shows the values that are associated with the units used. Most often, we see values 0.0821 and 8.314 used in this class.
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Re: Can R change?
Hi Ethan,
R is constant but the number can be different depending on the units. The three on the constants and formula sheet include R =8.314 J/K mol,
R=8.206 x 10^-2 L atm/ K mol, and R = 8.314 x 10^-2 L bar / K mol. I believe the one that is most common is the R=8.206 x 10^-2 L atm/ K mol because we often use R in the ideal gas law (PV=nRT) and you need units to cancel.
R is constant but the number can be different depending on the units. The three on the constants and formula sheet include R =8.314 J/K mol,
R=8.206 x 10^-2 L atm/ K mol, and R = 8.314 x 10^-2 L bar / K mol. I believe the one that is most common is the R=8.206 x 10^-2 L atm/ K mol because we often use R in the ideal gas law (PV=nRT) and you need units to cancel.
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Re: Can R change?
Since R is a constant, its "base"/"true" value cannot change but depending on the units being used the value of R can be different.
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Re: Can R change?
The actual value of R will stay the same, as it is a constant. However, the units of R are very important, so it's necessary to ensure the right cancellations can be made.
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Re: Can R change?
Initially, you'd think since R is a constant, it should not change.
BUT it's important to remember that it can be one of two values, depending on which units are used:
R = 8.3145 if using units of J / mol K
OR
R = 0.0821 if using units of atm L / mol K
BUT it's important to remember that it can be one of two values, depending on which units are used:
R = 8.3145 if using units of J / mol K
OR
R = 0.0821 if using units of atm L / mol K
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Re: Can R change?
Since R is a constant, it is a value that does not change. We can change this value's units, depending on the situation we want to use it in, but we cannot change R itself.
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Re: Can R change?
It depends what you are solving for! Whether it is in atm or J and change the R constant accordingly.
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Re: Can R change?
i think that there's two values of R that are both constants and used when they are fitting the units of the problem.
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Re: Can R change?
R is a constant so the actual value does not change but the form that is used depends on what units the problem is in.
Re: Can R change?
The R-value you will use for problems with the ideal gas equation depends on the units of the other terms in the equation. The different R-values and their units are laid out in the constants and equations sheet!
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Re: Can R change?
The constant R only changes depending on which units you are using. For example, if we were to calculate energy (J) R would be 8.314J/(K mol), but if we are using the law of ideal gas, then R would be 0.0821 (L atm)/(K mol).
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Re: Can R change?
Hi Ethan,
R changes based on the units used. However, because it is a constant, the values corresponding to the different units should be equivalent.
R changes based on the units used. However, because it is a constant, the values corresponding to the different units should be equivalent.
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Re: Can R change?
R is a constant with two possible values, the value you use depends on the question.
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Re: Can R change?
Because R is a constant, the value you use is dependent on which units you are given/ looking for
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Re: Can R change?
For most cases R is constant, but you will have to know which constant to use based on a given problem and the desired units.
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Re: Can R change?
R is a constant, but there are different values of it for different units, so you would use the R value specific to the units given in each problem.
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Re: Can R change?
The only conditions that would require us to change the value of R would be to match the units given in the problem. However, besides this condition the R value is constant and therefore should not change.
Re: Can R change?
No, but definition, R is the gas constant. While it never changes, its value can be different based on what units you are using. For example, the gas constant 8.314 has the units J.K^-1.mol^-1, so you would use that when you want an answer involving J.
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