Nitroglycerine

1
Nitroglycerine
100 g Nitro
3.193 mol gas
Or .110 mol O2 .661 mol
N2 1.10 mol H2O 1.32 mole CO2
2
Nitroglycerine
V nRT/P
PV nRT
3.193 mol
425 C
698 K
(0.082057 L atm/mol K)
V
V 183 L
3
H2 Cl2 ? 2HCl(g)
Limiting Reactant Problem the hard way
Final pressure pressure of HCl pressure of
excess reagent
g of Cl2
g of H2

• Starting moles H2
• Moles H2 used
• Excess moles H2

Moles Cl2
Moles H2 used
PV nRT

Moles HCl
Moles H2 xs
Total moles of gas
P 193 torr
4
H2 Cl2 ? 2HCl(g)
Understanding Gases the easy way
Remember that the composition of a gas does NOT
effect the pressure it exerts. So, since there
is no change in the number of MOLES of gas during
the reaction, there will be no change in the
pressure. Thus the initial pressure equals the
final pressure.
Final pressure Initial P P Cl2 P H2
g of Cl2
g of H2
5
Stoichiometry

A
B
C
D

Balanced Eq
Moles A
6
Gas Stoichiometry

A
B
C
D

Gases only!!!!
g of A
FW
Balanced Eq
Moles A
7
What is RMS for H2 at room temp?

8
What is RMS for H2 at room temp?

9
What is RMS for H2 at room temp?

1kg _ 1000g
2.0g/mol
1.92 x 103 m/s 2000 m/s 4300 mi/hr
10
Why does it take so long to smell gas that is
released in the same room?
11
Problems involving Gases

• PVnRT can be used to get moles of gas from P, V
  and T. Once you have mole then it is just a
  normal limiting reagent or stoichiometry or
  titration or .

12
Gas Law Shortcuts

• All revolve around the fact that in gases, V and
  P does NOT depend on nature of gas.
• Implications
• Can sum moles of all products and then find P or
  V. (Daltons Law of Partial Pressures.)
• Ratio of nV or nP is constant (at a given temp
  and P or V) So 2 moles of gas C takes up twice
  the volume of 1 mole of gas A at the same
  conditions.
• Caution Shortcuts are NOT always present.

13
Polarity and IMF

• Polarity is the key to IMFs.
• Select 2 molecules involved, find polarity of
  each.
• Polar/polar dipole/dipole -strongest
• Nonpolar/nonpolar induced/induced - strongest
• Polar / Nonpolar dipole induced-dipole
  -strongest
• If dipole/dipole look for H-Bonding
• Requires

14
Why dont oil and water mix?