What volume is occupied by 1.4 g of He at 25°C and a pressure of 773 mm Hg?
you dont have to solve it..just tell me the steps please ( practice for a test)
you dont have to solve it..just tell me the steps please ( practice for a test)
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v=nRT/P
m= 1.4 x 1mol of he/ 4 g of he ==0.35 mol of he
T= 25+273= 298k
P= 773mmhg x 1 atm/760 mmhg ===1.02 atm
v= 0.35x0.08206x298k/ 1.02 atm
v=8.39 L
Sig fig===8.4L if the mass has 2 sig figs as u say it does
please do not fall for these idiots...... to find volume u must use R=0.08206Latm/mol K NOT 8.3145m^3pa/ mol K..... thats wrong!!!!! u need L for volume not metres cube... and u dont wanna do conversions to make atm into pascals..... and below the idiot below the idiot below me... says kJ for R constant.... which is ******* stupid!!
m= 1.4 x 1mol of he/ 4 g of he ==0.35 mol of he
T= 25+273= 298k
P= 773mmhg x 1 atm/760 mmhg ===1.02 atm
v= 0.35x0.08206x298k/ 1.02 atm
v=8.39 L
Sig fig===8.4L if the mass has 2 sig figs as u say it does
please do not fall for these idiots...... to find volume u must use R=0.08206Latm/mol K NOT 8.3145m^3pa/ mol K..... thats wrong!!!!! u need L for volume not metres cube... and u dont wanna do conversions to make atm into pascals..... and below the idiot below the idiot below me... says kJ for R constant.... which is ******* stupid!!
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uhhh...ya i noticed that mistake too though...thanx Jay
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You will need to use the ideal gas equation since He is an ideal gas
PV = nRT
pressure is given to be 773 mmHg, you will need to convert this to Pa knowing that 133.32 Pa = 1 mmHg
R = 8.314 (Pa*m^3)/(mol*K)
T = 25deg C, which will need to be converted to Kelvin
the last thing you need is n, the moles of He. So go to the periodic table and find the molecular weight for helium. This will be in grams/mole. Divide the given mass 1.4g by the MW of helium to find moles of helium.
Now solve for volume V = (nRT)/P
PV = nRT
pressure is given to be 773 mmHg, you will need to convert this to Pa knowing that 133.32 Pa = 1 mmHg
R = 8.314 (Pa*m^3)/(mol*K)
T = 25deg C, which will need to be converted to Kelvin
the last thing you need is n, the moles of He. So go to the periodic table and find the molecular weight for helium. This will be in grams/mole. Divide the given mass 1.4g by the MW of helium to find moles of helium.
Now solve for volume V = (nRT)/P
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Use the Formula
PV = mRt
P = Pressure (kPa)
V = Volume (m^3)
M = mass (kg)
R = gas constant ( kJ/ kg-K)
t = temperature ( kelvin)
degree kelvin = degree celsius + 273
gas constant of helium = 2.077 kJ / kg-K
i already gave you the given. just substitute the given and do the computation and a little conversion of pressure.
hope that i helped
enjoy! ^_^
PV = mRt
P = Pressure (kPa)
V = Volume (m^3)
M = mass (kg)
R = gas constant ( kJ/ kg-K)
t = temperature ( kelvin)
degree kelvin = degree celsius + 273
gas constant of helium = 2.077 kJ / kg-K
i already gave you the given. just substitute the given and do the computation and a little conversion of pressure.
hope that i helped
enjoy! ^_^
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PV = nRT
p = pressure, in atm not mmHG
Convert mm Hg to atm
V = your unknown! Must be in liters...
n = moles. Convert grams of Helium to moles of Helium here.
R = gas constant. USE CORRECT UNITS. I typically stick to 8.314 J/kmol
T: stick to K until you know whatcha doin with the units. 1 degree C = 273.15 K
Convert from 25 C to K!
plug all of it in
https://docs.google.com/viewer?a=v&q=cac…
p = pressure, in atm not mmHG
Convert mm Hg to atm
V = your unknown! Must be in liters...
n = moles. Convert grams of Helium to moles of Helium here.
R = gas constant. USE CORRECT UNITS. I typically stick to 8.314 J/kmol
T: stick to K until you know whatcha doin with the units. 1 degree C = 273.15 K
Convert from 25 C to K!
plug all of it in
https://docs.google.com/viewer?a=v&q=cac…