Is the temperature proportional to the number of moles in a thermodynamic system?
No. Temperature is an intrinsic property of materials, meaning that the temperature does not depend on the amount of substance present. A cup (250 mL) of boiling water will have the same temperature as a gallon (~4L) of boiling water.Temperature is proportional to the average kinetic energy of the atoms/molecules in a system. The higher the average kinetic energy, the higher the temperature.
Mole to volume proportion, finding volume at STP, volume and temperature proportion?
If volume is 10L , mol of Ar = 10/7.0*0.04 = 0.057 mol Is that the answer: NO!!. Read the question: How many moles argon must be added......., You must add 0.057-0.040 = 0.017 mol Ar to be added. B is the correct choice Question 2 : First you need the vapour pressure of water at 50°C. This is 92.3mmHg at 50°C This is 92.3/760 = 0.12atm . Pressure of dry gas = 1.20-0.12 = 1.08atm Now use combined gas equation to find volume : Temp in K 50°C = 323K P1V1/T1 = P2V2/T2 1.0*V1/273 = 1.08*550/323 V1*323 = 273*1.08*550 V1 = 502mL Correct choice is A) 501 mL - the small difference of 1mL could result from a different value for the vapour pressure of water. Use combined gas law - ignore P which is assumed constant V1/T1 = V2/T2 Use same units for volume - 500mL = 0.5L and temp in K , 25°C = 298K 0.5/298 = 1.20/T2 T2*0.5 = 298*1.20 T2 = 298*1.20 /0.5 T2 = 714K T2 - 715-273= 442°C Answer is choice B) You get 60°C because you are not using temp ion K in your equation: You are saying : 1.2/0.5 *25 = 60 which is wrong As You see I am using 1.2/0.5*298 = 714K - which is correct.
How can equal volumes of all gases contain equal numbers of molecules if the size of molecules of different gases are different?
Avogadro's law states that, "equal volumes of all gases, at the same temperature and pressure, have the same number of molecules".For a given mass of an ideal gas, the volume and amount (moles) of the gas are directly proportional if the temperature and pressure are constant.which can be written as:[math]{\displaystyle V\propto n\,}[/math]or[math]{\displaystyle {\frac {V}{n}}=k}[/math]where:V is the volume of the gasn is the amount of substance of the gas (measured in moles).k is a constant equal to RT/P, where R is the universal gas constant, T is the kelvin temperature, and P is the pressure. As temperature and pressure are constant, RT/P is also constant and represented as k. This is derived from the ideal gas law.This law describes how, under the same condition of temperature and pressure, equal volumes of all gasescontain the same number of molecules. For comparing the same substance under two different sets of conditions, the law can be usefully expressed as follows:[math]{\displaystyle {\frac {V_{1}}{n_{1}}}={\frac {V_{2}}{n_{2}}}}[/math]The equation shows that, as the number of moles of gas increases, the volume of the gas also increases in proportion. Similarly, if the number of moles of gas is decreased, then the volume also decreases. Thus, the number of molecules or atoms in a specific volume of ideal gas is independent of their size or the molar mass of the gas.
Why, at constant volume for a fixed number of moles of a gas, does the pressure of a gas increase with increase in temperature?
Question “why at constant volume for a fixed number of moles of gas does the pressure increase with increase in temperature.”Assuming you don't have a pressure cooker in you home, but if you doYou can see that in a pressure cooker the volume of gas inside the cooker remains same while when we increase it's temperature gas tends to come out of it. Why ?Due to the increased volume of the gas at increasing the temperature.Now since you dont have a pressure cooker let's take a seasonal exampleDuring summer due you feel suffocated and just want to take all clothes out sit under any cooling source, why?Because due to increase in temperature the pressure applied onto your body has increased and therefore you start feeling suffocation.You will have at least experienced one of them.
It is known that volume of a gas is equal to 22.4L at STP and NTP. How can the volume of an ideal gas be different at different temperatures?
Basically, heat is random kinetic energy. Think of the gas in a box. As you raise the temperature of the gas, the molecules go faster, which means if they hit the walls of a fixed volume, they exert greater pressure on them. But if the gas must remain at constant pressure, that means the volume has to increase, effectively spreading the change of momentum of the gas particles striking the walls over greater area. Now take away the box. The gas will still do the same thing, except the molecules don't get stopped by a wall. The greater the kinetic energy, the more volume they need to maintain constant pressure.
Is the density of gas always proportional to the molar mass of its molecules?
The relationship between gas density and molar mass is directly derivable from the ideal gas equation.PV = nRTThe number of moles is equal to the mass of the gas (m) divided by the molar mass (M), so[math]PV = \frac{m}{M}RT[/math]Now rearrange:[math]\frac{m}{V} = \frac{PM}{RT}[/math]The left side, mass over volume, is density, and you can see that it is proportional to the molar mass (M), as long as P and T are constant.You can’t get the same relationship from the van der Waals equation of state, which more accurately models a real (as opposed to ideal) gas.So ideal gases, yes, density is proportional to molar mass.Real gases, no. Close, but no.
What is the relationship between the volume of a gas and the number of moles?
There is the ideal gas law where: n = PV / RT n is # mol P is pressure (atm) V is volume (L) R is a constant 0.0821 T is temperature in K So if the number of moles increases, and all other variables are held constant, the volume will also increase by the same factor.
True or False The pressure of a gas is directly proportional to the number of gas molecules present.?
assuming the gases are "ideal".. ************** 1).. FALSE..... yes... PV = nRT -----> P = n RT/V.... yes... at constant T and V.... P = k x n and therefore P is directly proportional to the amount of gas present.. BUT you didn't state that that T and V are constant... P is directly proportional to the product of n x T / V. . NOT JUST Temp!!!! And avogadros law is this anyway... "for two samples of an ideal gas AT THE SAME TEMPERATURE AND PRESSURE, volume is proportional to the number of gas molecules present" V1/n1 = V2/n2...not.. .P1/n1 = P2/n2 ********* 2).. FALSE PV = nRT V = (R/P) x n x T if R/P is costant... V = k x n x T and volume is directly proportional to the product of n x T.. IF n is held constant.. and again that wasn't specified then V is directly proportional to T and this is false anyway. ********* 3) BOTH TRUE AND FALSE... there are multiple different "standard temperature and pressure" is use today.. see the list here http://en.wikipedia.org/wiki/Standard_co... see the list... NIST is the most common in North America chemistry classes with T = 0°C = 273.15K P = 1 atm = 760mmHg = 760 torr but some teachers are teaching the IUPAC version. Making this one of those teacher dependant problems. You will need to ask!