Chemistry: Bellringer
1.)
Look over study guide. Any questions or
problems on sections I-III.
2H2 + O2
2H2O
Daily Agenda
• Review IV - VI
– Will be brief so time for practice
• Independent study time
• Monday 1st period
– I will be available for questions
• Room 413
IV. Stoichiometry
• Read problem
– Figure out starting information
– Figure out units of answer
• Determine conversion factors
– Molar masses, coefficients for balanced reactions
• Draw out fence
– Double check units cancel
• Calculator time
Practice Problem
• If you start with 20 g LiOH, how much
LiCl could you produce?
LiOH + KCl
LiCl + KOH
Given information:
Starting LiOH = 20 g LiOH
Balanced reaction
Conversions
• Steps of calculation
– Grams LiOH to moles LiOH to moles LiCl to gram
LiCL
• Grams to moles
– Needs molar mass of LiOH and LiCl
• LiOH = ________
• LiCl = _________
• Moles to moles
– Need coefficients from balanced reaction
• 1 mole LiOH = 1 mole LiCl
Fence
g LiOH
mol LiOH
mol LiCl
g LiCl
g LiOH
mol LiOH
mol LiCl
mol LiOH
x
g LiOH x g LiOH
mol LiCl
mol LiOH
x
g LiCl
mol LiCl
Answer
In g LiCl
Answer
= In g LiCl
Gas Laws
P1V1=P2V2
V1/T1=V2/T2
(constant T, n)
(constant P, n)
Boyle’s Law
P1V1 P2V2
=
T1
T2
Charles’ Law
PV = nRT
(R = 0.00821 L atm/mol K)
(constant n)
Combined Gas Law
Ideal Gas Law
Acids and Bases
• Acids
– Donate protons
• Bases
– Accept protons
+
mol
H
+
pH = !log(concentration H ) = !log(
)
L
Independent Work Time
• Get to it.
• Remember bring sheets.