gas law, temperature pressure, moles and volume

1. Recitation #14
• Chapter 9:
• Hybridization, bond angles, orbital overlap
• Multiple bonds
• Chapter 10:
• Gas Laws, relationship between temperature, pressure,
moles and volume of a gas
• Please fill out course survey!
• Good luck on exam 4!
College of Arts & Sciences - Chemistry

2. C atom (ground state)
2s
2p
Energy
1s
Hybridization
-For a covalent bond to form, we need to
orbitals from two different atoms. Each orbital
needs to contain one electron.
-Based on the electron configuration of carbon,
we would think it could only form 2!! Bonds, and
yet it forms 4!
How can we explain this?

3. Hybridization
College of Arts & Sciences - Chemistry
sp3
1s
C atom (hybridized)
C atom (ground state)
2s
2p
Energy
1s
Carbon needs 4 identical orbitals that each contain one
electron, to create these 4 hybrid orbitals we blend 4 atomic
orbitals (s+p+p+p). Creating 4 identical sp3 hybrid orbitals

4. Hybridization
College of Arts & Sciences - Chemistry
sp2
1s
C atom (hybridized)
C atom (ground state)
2s
2p
Energy
1s
-If carbon has 3 electron domains, it will be sp2
hybridized, blending 3 atomic orbitals (s+p+p) to
create 3 identical sp2 hybrid orbitals. One atomic p
orbital remains unhybridized.
-An electron is assigned to the lone p orbital, even
though it is higher in energy than the sp2 orbitals.
-Forming the pi bond is exothermic, releasing more
energy than is required to have an electron in 2p
orbital.
2p

5. Hybridization
College of Arts & Sciences - Chemistry
sp2
1s
C atom (hybridized)
2p (used to form pi bond)
(used to form sigma bonds)

6. Hybridization
College of Arts & Sciences - Chemistry
How many pi bonds are within the structure of this analog of penicillin?

7. Hybridization
College of Arts & Sciences - Chemistry
How many lone pairs of electrons are found on this analog of penicillin?

8. Hybridization
College of Arts & Sciences - Chemistry
What is the hybridization, molecular geometry, and bond angles of C1 and C2?
What orbitals are used to make the sigma and pi bond between C1 and C2?

9. Hybridization
College of Arts & Sciences - Chemistry
What is the hybridization, molecular geometry and bond angles of C3 and N4?
What orbitals are used to hold the lone pair of electrons on N4?

10. Hybridization
College of Arts & Sciences - Chemistry
What is the hybridization, molecular geometry and *expected* bond angles
of C5?
What orbitals are used to make the sigma bond between C5 and H6?

11. Hybridization
College of Arts & Sciences - Chemistry
What orbitals contain the lone pair electrons on S10?
What is the hybridization, molecular geometry, and bond angles of O9?

12. Hybridization
College of Arts & Sciences - Chemistry
What orbitals are used to hold the lone pair electrons on O9?
What orbitals are used to make the sigma bond between O9 and H12?

13. Hybridization
College of Arts & Sciences - Chemistry
What is the hybridization, molecular geometry, and bond angles of C1 and C2?
What orbitals are used to make the sigma and pi bonds between C2 and C3?

14. Gas Laws
College of Arts & Sciences - Chemistry
Sodium azide (NaN3) is used in many car airbags. The
impact from a collision triggers an electrical shock
which initiates the decomposition of NaN3 following
the reaction outlined below.
2NaN3(g) 2Na(s) + 3N2(g)
The N2 quickly inflates and fills the airbag, protecting
the driver. What volume of N2 would be
produced at 30.0 ℃ and 1.18 atm
from 75.0 grams of NaN3

15. Gas Laws
College of Arts & Sciences - Chemistry
2NaN3(g) 2Na(s) + 3N2(g)
What volume of N2 would be produced at 30.0 ℃ and
1.18 atm from 75.0 grams of NaN3
PV = nRT
R = 0.0821 (L*atm/mol*K)

16. Gas Laws
College of Arts & Sciences - Chemistry
While resting, the average 68-kg person consumes
14.0 L of pure O2 per hour at 25.0 °C and 0.9869 atm.
How many moles of O2 are consumed in 1 hour?
PV = nRT
R = 0.0821 (L*atm/mol*K)

17. Need to Know
College of Arts & Sciences - Chemistry
• Electron domain geometries
• molecular geometries
• Hybridization
• Associated Bond angles
• Relationships between temperature, pressure, moles and volume
of gasses