Created using AIStandard Temperature and Pressure (STP) is crucial for gas calculations, defined as 0°C (273.15 Kelvin) and 1 atmosphere of pressure. At STP, one mole of an ideal gas occupies a standard molar volume of 22.4 liters. This establishes a direct relationship between the amount of gas in moles and its volume in liters, serving as a conversion factor for gas-related computations. Remember, the volume of any ideal gas at STP can be determined using the equation:
where 'n' is the number of moles, 'R' is the ideal gas constant, 'T' is the temperature in Kelvin, and 'P' is the pressure in atmospheres.
In order to accurately study the effect that changes in pressure, temperature and moles have on volume, chemists will often run their experiments under Standard Temperature and Pressure.
Standard temperature and pressure, abbreviated as STP, is a commonly used term in calculations involving gases. Now we're going to say STP. The temperature is measured as either 0�C or 273.15 K.
Now we know that when we're dealing with gas calculations we tend to go with Kelvin. Now the pressure at STP is 1 atm, so just remember when you hear STP it means 273.15 K and for pressure one atmosphere.
Here in this example question, it says a sample of oxygen gas has a measured volume of 325 MLS at STP. How many grams are present? All right, so here they're giving us volume in the forms of milliliters. An STP is giving us temperature plus pressure. We know from the ideal gas law with these values given to us or these variables given to us. The only thing that's missing is our moles, because we have a volume already, we have pressure and temperature, and we always know what R is.
So we're going to divide OPT RT and when we do that we're going to get our moles. Moles here will equal pressure times volume over R * T. At STP our pressure is 1 atmosphere. Our volume we just change milliliters to liters, so 0.325 liters. We have our R constant which is .08206 liters times atmospheres over moles times K. Then remember we're dealing with temperature at T we use the units of Kelvin. So that's 273.15 Kelvin.
So here, Kelvin's cancel out, liters cancel out, atmospheres cancel out, and we'll be left with the moles of our oxygen gas. When we plug that in, we get 0.01450 moles of O2. But here the question is not asking us to determine the moles of oxygen gas, but instead the grams of oxygen gas. So we just need to do a simple conversion. We say that for every one mole of O2, it weighs 32g because there's two oxygens. Those cancel out and what we get at the end is 0.464 grams of O2.
Here our answer has three significant figures because the value of 325 has three significant figures as well. So just remember when we're faced a question like this, look and see what variables are given. Since we're dealing with the ideal gas law, we see that the value that's missing is moles. Then go for moles to grams to get your final answer.
With the idea of SDP, we are faced with a new idea, the standard molar volume. Now we're going to say that it represents the volume of 1 mole of an ideal gas at STP. All right. So here we're going to say
volume = moles × RT PWe're dealing with one mole of the gas. R is just our constant, and we're going to say we're dealing with STP.
So our pressure will be 273.15 Kelvin and our pressure will just simply be one atmosphere. We see here that the moles cancel out, Kelvin's cancel out, atmospheres cancel out. So here we'll have our volume in liters. When we plug this in, we get 22.24 liters. This would represent our standard molar volume for one mole of gas, an ideal gas.
Now this helps to establish a relationship between moles and volumes. And because we have a relationship between mole and volumes, we can create a new conversion factor. And that conversion factor would be that for any one mole of an ideal gas at STP, its molar volume would be 22.4 liters. So just remember, if we're dealing with STP and we're dealing with one mole of any gas, then its standard molar volume will be 22.4 liters.
Here are the example question says how many moles of chlorine gas occupy a volume of one 5.7 liters at STP. All right, so here they're talking about determining the moles of an ideal gas. They're giving us the volume of of that gas at STP. Here we can use the conversion factor that we know exists with standard molar volume.
We're going to say we have 15.7 liters, and we're going to say here that the conversion factor is for every one mole of any gas at STP, the volume is 22.4 liters. Here liters cancel out and I'll have my moles which comes out to 0.701 moles of Cl2. So this is one way that we get our answer.
What else we could do is we could have also said that we have 15.7 liters which is our volume and then we have STP which is pressure and temperature. We could have said that our moles equals PVRT and we would have gotten the same exact answer because here this would have been one atmosphere. This here is 15.7 liters.
Then here we have our R constant with its units. Don't forget the units times temperature at STP is 273.15 Kelvin and if we worked it out we get the same exact moles for Cl2. So just realize that there's two ways that we can approach a question like this. Using it with the conversion factor of 1 mole for every 22.4 liters, or by using it through the traditional means with the ideal gas law.
A sample of dichloromethane gas (CH2Cl2) occupies 32.6 L at 310 K and 5.30 atm. Determine its volume at STP?
Which gas sample has the greatest volume at STP?
Nitrogen and hydrogen combine to form ammonia via the following reaction:
1 N2 (s) + 3 H2 (g) → 2 NH3 (g)
What mass of nitrogen is required to completely react with 800.0 mL H2 at STP?
What is standard temperature and pressure (STP)?
Standard Temperature and Pressure (STP) is a reference point used in chemistry to provide a set of conditions for experiments and calculations. At STP, the standard temperature is defined as 0 degrees Celsius (273.15 Kelvin), and the standard pressure is 1 atmosphere (atm), which is equivalent to 101.325 kilopascals (kPa). These conditions are important because they provide a baseline that can be used to compare different chemical reactions and properties of substances. For instance, at STP, one mole of an ideal gas occupies 22.414 liters of volume. This reference is crucial for calculations involving gas laws and behaviors under controlled conditions. It's essential to note that STP is different from the standard ambient temperature and pressure (SATP), which uses a temperature of 25 degrees Celsius and a pressure of 100 kPa.
Created using AIWhat volume will one mole of a gas occupy under standard temperature and pressure?
Under standard temperature and pressure (STP), which is defined as a temperature of 0°C (273.15 K) and a pressure of 1 atmosphere (atm), one mole of an ideal gas occupies a volume of 22.414 liters. This is known as the molar volume of a gas, and it's a consequence of the Ideal Gas Law when applied to STP conditions. The Ideal Gas Law is:
where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin. When you plug in the values for STP (P = 1 atm, T = 273.15 K, and n = 1 mole), and use the appropriate value for R (0.0821 L·atm/mol·K), you can solve for V, which gives you the volume of the gas.
Created using AIWhat are the standard temperature and pressure values for sea level?
Standard temperature and pressure (STP) values for sea level are commonly used as reference points in physics and chemistry. The standard temperature is defined as 0 degrees Celsius (273.15 Kelvin), which is the freezing point of water. The standard pressure is defined as 1 atmosphere (atm), which is equivalent to 101.325 kilopascals (kPa) or 760 millimeters of mercury (mmHg). These values are important because they provide a baseline for scientists and engineers to compare different sets of experimental data. When working with gases, for example, STP conditions allow for the use of the Ideal Gas Law to predict the behavior of a gas under these standard conditions.
Created using AI