Stoichiometry
Jan 14, 2016
Stoichiometry. Balanced Equations. All stoichiometry problems start with a balanced equation. You must check for this! If it is not balanced, BALANCE IT!. Reviewing Balancing Equations. S. Fe. Fe 2 S 3. S. Fe. S. Can change coefficients but CANNOT change subscripts Example - PowerPoint PPT Presentation
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
All stoichiometry problems start with a balanced equation.
You must check for this!
If it is not balanced, BALANCE IT!
Can change coefficients but CANNOT change subscripts
Example◦ 3S + 2 Fe Fe2S3
S
S
S
Fe
Fe
Fe2S3
Al + CuO Al2O3 + Cu
____________________________
H2 + O2 H2O
_______________________
Remember what an equation actually means◦ Mg + S MgS◦ One _____________reacts with one ___________
creating one formula unit of MgS But
◦ This also means that one mole of _________ reacts with one mole of ___________ to form one mole of _______ formula units.
◦ 1 mol Mg, 1 mol S, and 1 mol MgS are stoichiometry equivalents
What about the equation
◦ C3H8 + 5O2 3CO2 + 4H2O
◦ Now, ____ mol C3H8, _____ mol O2, _____ mol CO2, and _______ mol H2O are stoichiometry equivalents
As stoichiometry equivalents, they can be used in a conversion factor
__________________ Conversion Factors
◦ One equivalent is placed on top and one on bottom
◦ Allows us to move from one compound to another in a balanced equation
Given the equation: MgCl2 + 2 AgNO3 Mg(NO3)2 + 2 AgCl
What is the mass of AgCl produced if 24g of MgCl2 is reacted with excess AgNO3?
What amount of MgCl2 will react with 3.85 g AgNO3?
So far we have been assuming that we have an excess of all the other reactants
This is not often true….often you have a set amount of both reactants◦ Each amount would lead you to a different
amount of product◦ Must use the number that is ___________
Given the equation: MgCl2 + 2 AgNO3 Mg(NO3)2 + 2 AgCl
How much AgCl will be produced if 28g of MgCl2 is reacted with 51g of AgNO3?
Yield is the amount of product that you get from a reaction
Theoretical yield is the amount that you should get based on using stoichiometry
Actual yield is the amount of product actually attained during an experiment
Calculated by taking
◦ _____________________________________
Given the equation: MgCl2 + 2 AgNO3 Mg(NO3)2 + 2 AgCl
What is the percent yield of Mg(NO3)2 if 168.4 g of AgNO3 is reacted to produce 47.2g of Mg(NO3)2?
Related Documents
