Download - Chapter 12
Chapter 12
Stoichiometry
Reaction – Stoichiometry Problems
Identify the information given
Identify the unknown, the information you are expected to find.
Given Unknown
Given amount in moles
Mole to Mole Ratio
Unknown amount in moles
Given amount in grams (A)Given amount in moles (A)
Mole B / Mole A
Unknown amount in moles (B)
Given amount in grams (A) Molar Mass AGiven amount in moles (A)
Mole B / Mole A
Unknown amount in moles (B)
Grams A
Moles A
Moles B
Grams A
Moles A
Moles B
Grams B
Grams A Molar Mass A
Moles A Mole B/ Mole A
Moles B Molar Mass B Grams B
Problem
In photosynthesis, plants use energy from the sun to produce glucose, C6H12O6, and oxygen from the reaction of carbon dioxide and water.
What mass, in grams, of glucose is produced when 3.00 moles of water react with carbon dioxide?
Answer 3.00 mole H2O
x 1 mole C6H12O6 =
6 mole H2O
x 180.16 g C6H12O6 = 90.1 g C6H12O6
1 mole C6H12O6
Problem NH3(g) + O2(g) NO (g) + H2O (g)
Balance this equation!!
If the reaction is run with 824 g of NH3, and excess oxygen, how many moles of NO and H2O are formed?
Answer 4NH3(g) + 5O2(g) 4NO (g) + 6H2O (g)
824 g x 1 mole NH3 x 4 mole NO
17.031 g NH3 4 mole NH3
= 48.4 mole NO
Answer
824 g x 1 mole NH3 x 6 mole H2O
17.031 g NH3 4 mole NH3
= 72.6 mole H2O