moe darklight
Nov7-09, 02:22 AM
1. The problem statement, all variables and given/known data
Assuming ideal gas behaviour, what would be the density of gaseous ethane (C2H6) at 30. °C and 771 mmHg?
2. Relevant equations
Ideal gas laws.
I'm using:
Density = MP/RT (M is g/mol)
3. The attempt at a solution
This is one of the questions due online by Sunday night. They're marked by the computer, and we get only a limited number of tries. Anyway, this is my answer and how I arrived at it:
-- M = 2*16+6*1.008 = 38.048 g/mol
-- T = 30 + 273.15 = 303.15 K
-- P = 771/760 = 1.014 atm
-- R = 0.0821 atm*L/mol*K
=> d = MP/RT = (38.048*1.014)/(0.0821*303.15) = 38.43/24.88 = 1.54 g/L
I've tried rounding to 2 digits, to 3 digits... every possible combination. I've gone over the numbers a bazillion times and it keep telling me I'm wrong, and I have 1 try left. What am I doing wrong?
Assuming ideal gas behaviour, what would be the density of gaseous ethane (C2H6) at 30. °C and 771 mmHg?
2. Relevant equations
Ideal gas laws.
I'm using:
Density = MP/RT (M is g/mol)
3. The attempt at a solution
This is one of the questions due online by Sunday night. They're marked by the computer, and we get only a limited number of tries. Anyway, this is my answer and how I arrived at it:
-- M = 2*16+6*1.008 = 38.048 g/mol
-- T = 30 + 273.15 = 303.15 K
-- P = 771/760 = 1.014 atm
-- R = 0.0821 atm*L/mol*K
=> d = MP/RT = (38.048*1.014)/(0.0821*303.15) = 38.43/24.88 = 1.54 g/L
I've tried rounding to 2 digits, to 3 digits... every possible combination. I've gone over the numbers a bazillion times and it keep telling me I'm wrong, and I have 1 try left. What am I doing wrong?