Question

What is the pressure in millimeters of mercury of 0.0155 mole of He gas with a volume of 206 mL at a temperature of 30 degrees C?

I used the ideal gas law and ended up with 1.87 mmHg but it said that was wrong. Please help.

Answer 1

I am wondering
1) if you changed temp to kelvins
2 if you used the right gas constant (units in ml Kelvin mmhg)

Answer 2

Here's how I worked it:
P= ?
n= 0.0155 mol
v=206mL so .206L
t=30C +273 is 303K
then

0.0155mol *0.0821 L*atm/mol*K *303K divided by .206L which gives you 1.87 mmHg
What did I do wrong?

Answer 3

thanks! Duh! Got it! Yippie!

Answer 4

yep, you solved it in atm.