given 1000 mL of helium at 15degrees C and 763mmHg, determine its volume at -6degrees C and 420 mmHg.

my friend said she got 1.68 x 10^3 mL

help, I have no idea how she got it

1 answer

She used the ideal gas law, PV = nRT

You can use it in the form PV/T = constant or

V2/V1 = T2/T1 * P1/P2

The temeratures must be absolute (Kelvin)
V2/1000 = 266/288 * 763/420 = 1678 mL

Round it off to 1680