st.patrick regional sec
chemistry 11, block a
chemistry 11, block a
Thursday, October 29, 2009 8:32 PM
Today after we learned about the Molar Masses, we then move over to the Gases and Moles. If is easy for most of us if we know what we are doing.
Gases and Moles
Gases and Moles
- The volume of a balloon occupied by a certain gas depends on the temperature and pressure
Standard Pressure and Temperature (STP)
*0 degrees Celsius(273 K) and 101.3 kPa*
Standard Ambient Temperature and Pressure (SATP)
*25 degrees Celsius(298K) and 100 kPa*
The volume of 1.0 mole of any gas at STP is 22.4L
The molar volume at STP is 22.4L
22.4L/1 mol or 1 mol/22.4L
{At STP only}
Example 1: Find the volume occupied by 0.060 mol of CO2 gas at STP.
Answer: 0.060 mol x 22.4L/mol = 1.34L
Example 2: Find the number of moles in a 264.0 ml sample of NO2 at 0 degree and 101.3 kPa ml->L->mol
Answer: 264.0 ml x 1L/1000 ml = 0.264L x 1 mol/22.4L = 0.012 mol
Example 3: Find the volume occupied by 22.0g of CO2(g) at STP
g->mol->L
Answer: 1 C= 12.0
2 O= 32.0
44.0
22.0g x 1 mol/44.0g = 22.0 mol/44.0 = 0.5 mol x 22.4L/mol = 11.2 L
2 O= 32.0
44.0
22.0g x 1 mol/44.0g = 22.0 mol/44.0 = 0.5 mol x 22.4L/mol = 11.2 L
