HONORS CHEMISTRY
February 9, 2021
Unit 8: Stoichiometry
Pick up papers from Stoichiometry Unit
2 Na
+ Cl2
--> 2NaCl
2 g + 1 g = 2 g
(WRONG)
2 atoms + 1 molecule = 2
molecules (Correct)
2
mol + 1 mol
= 2 mol
(Correct)
2 Na +
Cl2
--> 2NaCl
100 g
x L
x g
x g NaCl = 100 g Na (1 mol
Na/23 g Na)(2 mol NaCl/2 mol Na)(58.5 g NaCl/1 mol NaCl) = 254 g
NaCl
[1 mol = Molar Mass = 6.02 x
1023 particles = 22.4 L @ STP]
x L Cl2 = 100 g Na(1 mol
Na/23 g Na)(1 mol Cl2/2 mol Na)(22.4 L Cl2/1 mol Cl2)
= 49 L Cl2
Use
Stoichiometry Island Diagram.
GIVEN: 2 TiO2 + 4 Cl2 + 3
C --> 1 CO2 + 2 CO
+ 2 TiCl2
a) How many moles of chlorine will react with 4.55 moles of
carbon?
(6.07
mol Cl2)
b) How many grams of titanium (IV) oxide will react with 4.55 mole of
carbon?
(242 g)
c) How many molecules "tickle-4" (TiCl4) can be produced from 115 g
"tyoto" (TiO2)?
(8.66 g x 1023)
d) How many
liters of CO can be made from 86 g of C?
(107 L)
GIVEN: 2 Ir + Ni3P2 --> 3 Ni + 2 IrP
a) If 5.33 x 1028 molecules of Ni3P2
react with excess Ir, how many grams of IrP are produced?
(3.98 x 107 g IrP)
b) How many grams of Ir will react with 465 g of Ni3P2?
(186 g Ir)
c) How many moles of Ni are produces id 8.7 x 1025 atoms of Ir
are consumed?
(217 mol Ni)
Allow ~15 minutes of class time to work on
Stoichiometry - Problem Sheet 1
pdf
LIMITING REACTANT
Example 1
N2
+ H2
--> NH3
100 g 100 g
X g
Answer: 121.38 g NH3
Example 2
X
+ 2Y
--> Z2 Z = 5 g/mol
50 L 2.4
x10
24
atoms X g
Answer: 20 g Z
Factors to consider: cost of reactants, disposal of
unused reactants.
dollars + cents
--> Products (want cents to be
excess and dollars to be limiting)
HW:
Vocabulary - Stoichiometry pdf
Stoichiometry - Problem Sheet 1 pdf
My crown is called content,
a crown that seldom
kings enjoy
- William Shakespeare