Monday, November 30, 2009
The Aufbau Principle - Electronic Structure and the Aufbau Principle
Stable atoms have as many electrons as they do protons in the nucleus. The electrons gather around the nucleus in quantum orbitals following four basic rules called the aufbau principle.
**no two electrons in the atom will share the same four quantum numbers n, l, m, and s.
**electrons will first occupy orbitals of the lowest energy level.
**electrons will fill an orbital with the same spin number until the orbital is filled before it will begin to fill of the opposite spin number.
**electrons will fill orbitals by the sum of the quantum numbers n and l. Orbitals with equal values of (n+l) will fill with the lower n values first.
The second and fourth rules are basically the same. The graphic shows the relative energy levels of the different orbitals. An example of rule four would be the 2p and 3s orbitals. A 2p orbital is n=2 and l=2 and a 3s orbital is n=3 and l=1. (n+l) = 4 in both cases, but the 2p orbital has the lower energy or lower n value and will get filled before the 3s shell.
**no two electrons in the atom will share the same four quantum numbers n, l, m, and s.
**electrons will first occupy orbitals of the lowest energy level.
**electrons will fill an orbital with the same spin number until the orbital is filled before it will begin to fill of the opposite spin number.
**electrons will fill orbitals by the sum of the quantum numbers n and l. Orbitals with equal values of (n+l) will fill with the lower n values first.
The second and fourth rules are basically the same. The graphic shows the relative energy levels of the different orbitals. An example of rule four would be the 2p and 3s orbitals. A 2p orbital is n=2 and l=2 and a 3s orbital is n=3 and l=1. (n+l) = 4 in both cases, but the 2p orbital has the lower energy or lower n value and will get filled before the 3s shell.
Electron Configuration
Electron Configuration
http://www.teachersdomain.org/assets/wgbh/phy03/phy03_doc_qmechatom/phy03_doc_qmechatom.pdf
The electron configuration of an atom denotes the distribution of electrons among available shells. The standard notation lists the subshell symbols, one after another. The number of electrons contained in each subshell is stated explicitly. For example, the electron configuration of beryllium, with an atomic (and electron) number of 4, is 1s22s2 or [He]2s2.
http://www.teachersdomain.org/assets/wgbh/phy03/phy03_doc_qmechatom/phy03_doc_qmechatom.pdf
The electron configuration of an atom denotes the distribution of electrons among available shells. The standard notation lists the subshell symbols, one after another. The number of electrons contained in each subshell is stated explicitly. For example, the electron configuration of beryllium, with an atomic (and electron) number of 4, is 1s22s2 or [He]2s2.
Electron Dot Configurations, Lewis Dot Structures, Bohr Model and VESPR Theory
Electron Dot Configurations
http://www.uoregon.edu/~ch111/L12.htm
Contructing Lewis Dot StructuresStarting with a structure indicating only atom connections (single bonds), you can practice constructing a Lewis dot structure. Just click on the atom or bond you wish to modify. Nonzero formal charges are indicated for each atom in the structure once the total number of electrons is correct.
A recommended procedure might be:
Count the total number of valence electrons (N) needed to account for the atoms (based on the column of the atom in the periodic table) and charge (add one electrons for each negative charge; subtract one electron for each positive charge).
Draw the framework with single bonds. Some knowledge of the way the atoms are connected may be required.
Using lone pairs, complete octets around the noncentral atoms.
Count the number of electrons depicted (two for each bond and two for each lone pair). If this number is less than N, then add electrons to the central atom until the total number of electrons depicted is N.
If the octet rule is not satisfied for the central atom and lone-pair electrons are nearby, use those electrons to make double or triple bonds to the central atom.
Check each atom to see if it has a formal charge. (Singly bonded oxygen will require a negative charge, for example.)
BOHR MODEL
http://csep10.phys.utk.edu/astr162/lect/light/bohr.html
VESPR THEORYhttp://cost.georgiasouthern.edu/chemistry/general/molecule/vsepr.htm
http://www.uoregon.edu/~ch111/L12.htm
Contructing Lewis Dot StructuresStarting with a structure indicating only atom connections (single bonds), you can practice constructing a Lewis dot structure. Just click on the atom or bond you wish to modify. Nonzero formal charges are indicated for each atom in the structure once the total number of electrons is correct.
A recommended procedure might be:
Count the total number of valence electrons (N) needed to account for the atoms (based on the column of the atom in the periodic table) and charge (add one electrons for each negative charge; subtract one electron for each positive charge).
Draw the framework with single bonds. Some knowledge of the way the atoms are connected may be required.
Using lone pairs, complete octets around the noncentral atoms.
Count the number of electrons depicted (two for each bond and two for each lone pair). If this number is less than N, then add electrons to the central atom until the total number of electrons depicted is N.
If the octet rule is not satisfied for the central atom and lone-pair electrons are nearby, use those electrons to make double or triple bonds to the central atom.
Check each atom to see if it has a formal charge. (Singly bonded oxygen will require a negative charge, for example.)
BOHR MODEL
http://csep10.phys.utk.edu/astr162/lect/light/bohr.html
VESPR THEORYhttp://cost.georgiasouthern.edu/chemistry/general/molecule/vsepr.htm
Chapter 15-16 Vocabulary
Chapter 16 covers the nature of Covalent Bonds, Bonding Theory, Polar Bonds, Polar Molecules, and VSEPR Theory. Electron dot and Lewis Structure will be important information from chapter 15 in helping students to draw and understand single, double and triple bonds.
Chapter 15
coordination number
metallic bond
electron dot structure
octet rule
halide ion
valence electron
ionic bond
Chapter 16 (16.1-16.2)
antibonding orbital
paramagnetic
bond dissociation energy
pi bond
bonding orbital
polar bond
coordinate covalent bond
polar covalent bond
diamagnetic
polar molecule
dipole
resonance structure
dipole interaction
sigma bond
dispersion force
single covalent bond
double covalent bond
structural formula
hybridization
tetrahedral angle
hydrogen bond
triple covalent bond
molecular orbital
unshared pair
network solid
van der waals force
nonpolar covalent bond
VSEPR theory
Chapter 15
coordination number
metallic bond
electron dot structure
octet rule
halide ion
valence electron
ionic bond
Chapter 16 (16.1-16.2)
antibonding orbital
paramagnetic
bond dissociation energy
pi bond
bonding orbital
polar bond
coordinate covalent bond
polar covalent bond
diamagnetic
polar molecule
dipole
resonance structure
dipole interaction
sigma bond
dispersion force
single covalent bond
double covalent bond
structural formula
hybridization
tetrahedral angle
hydrogen bond
triple covalent bond
molecular orbital
unshared pair
network solid
van der waals force
nonpolar covalent bond
VSEPR theory
Stoichiometry Review
For the questions on this worksheet, consider the following equation:
Ca(OH)2(s) + 2 HCl(aq) ---> CaCl2(aq) + 2 H2O(l)
1) What type of chemical reaction is taking place? _____________________
2) How many liters of 0.100 M HCl would be required to react completely with 5.00 grams of calcium hydroxide?
3) If I combined 15.0 grams of calcium hydroxide with 75.0 mL of 0.500 M HCl, how many grams of calcium chloride would be formed?
4) What is the limiting reagent from the reaction in problem #3? __________
5) How many grams of the excess reagent will be left over after the reaction in problem 3 is complete?
Solve the following stoichiometry grams-grams problems:
1) Using the following equation:
2 NaOH + H2SO4 ---> 2 H2O + Na2SO4
How many grams of sodium sulfate will be formed if you start with 200 grams of sodium hydroxide and you have an excess of sulfuric acid?
2) Using the following equation:
Pb(SO4)2 + 4 LiNO3 ---> Pb(NO3)4 + 2 Li2SO4
How many grams of lithium nitrate will be needed to make 250 grams of lithium sulfate, assuming that you have an adequate amount of lead (IV) sulfate to do the reaction?
Percent Yield Practice
1) Write the equation for the reaction of iron (III) phosphate with sodium sulfate to make iron (III) sulfate and sodium phosphate.
2) If I perform this reaction with 25 grams of iron (III) phosphate and an excess of sodium sulfate, how many grams of iron (III) sulfate can I make?
3) If 18.5 grams of iron (III) sulfate are actually made when I do this reaction, what is my percent yield?
4) Is the answer from problem #3 reasonable? Explain.
5) If I do this reaction with 15 grams of sodium sulfate and get a 65.0% yield, how many grams of sodium phosphate will I make?
Ca(OH)2(s) + 2 HCl(aq) ---> CaCl2(aq) + 2 H2O(l)
1) What type of chemical reaction is taking place? _____________________
2) How many liters of 0.100 M HCl would be required to react completely with 5.00 grams of calcium hydroxide?
3) If I combined 15.0 grams of calcium hydroxide with 75.0 mL of 0.500 M HCl, how many grams of calcium chloride would be formed?
4) What is the limiting reagent from the reaction in problem #3? __________
5) How many grams of the excess reagent will be left over after the reaction in problem 3 is complete?
Solve the following stoichiometry grams-grams problems:
1) Using the following equation:
2 NaOH + H2SO4 ---> 2 H2O + Na2SO4
How many grams of sodium sulfate will be formed if you start with 200 grams of sodium hydroxide and you have an excess of sulfuric acid?
2) Using the following equation:
Pb(SO4)2 + 4 LiNO3 ---> Pb(NO3)4 + 2 Li2SO4
How many grams of lithium nitrate will be needed to make 250 grams of lithium sulfate, assuming that you have an adequate amount of lead (IV) sulfate to do the reaction?
Percent Yield Practice
1) Write the equation for the reaction of iron (III) phosphate with sodium sulfate to make iron (III) sulfate and sodium phosphate.
2) If I perform this reaction with 25 grams of iron (III) phosphate and an excess of sodium sulfate, how many grams of iron (III) sulfate can I make?
3) If 18.5 grams of iron (III) sulfate are actually made when I do this reaction, what is my percent yield?
4) Is the answer from problem #3 reasonable? Explain.
5) If I do this reaction with 15 grams of sodium sulfate and get a 65.0% yield, how many grams of sodium phosphate will I make?
Bellringer 3
Using the equation below, calcuate the following:
Molar ratio
Molar mass
Mole to mole (given 2 moles of HBr)
Mole to gram (given 43 grams of HBr)
Gram to Percent Yield
HBr + ___ KHCO3 --->___ H2O + ___ KBr + ___ CO2
Molar ratio
Molar mass
Mole to mole (given 2 moles of HBr)
Mole to gram (given 43 grams of HBr)
Gram to Percent Yield
HBr + ___ KHCO3 --->___ H2O + ___ KBr + ___ CO2
Friday, November 20, 2009
Stoichiometry Tutoring Link
go to this link to assist you with solving stoichiometry problems.
http://www.chemtutor.com/mols.htm
http://www.chemtutor.com/mols.htm
More Stoichiometry problems-Homework 2
1a) How many moles of chlorine gas (Cl2) would react with 5 moles of sodium (Na) according
to the following chemical equation? (Balance equation.)
Na + Cl2 --> NaCl
1b) Using the equation (after it is balanced) above, determine the amount of product that can be
produced from 24.7 g Na.
1c) How many molecules of product would be produced from 24.7g Na?
__________________________________________________________________________________
2a) In the reaction 2C8H18 + 25O2 --> 16CO2 + 18 H2O, the ratio of volumes of O2 to CO2
is _________________.
2b) If 27.3g of C8H18 are combusted, what mass of water will be produced?
2c) How many molecules of CO2 will be produced?
2d) How many atoms of H are in 2 mol of C8H18?
2e) What is the percentage, by mass, of the H in 2 mol of C8H18?
to the following chemical equation? (Balance equation.)
Na + Cl2 --> NaCl
1b) Using the equation (after it is balanced) above, determine the amount of product that can be
produced from 24.7 g Na.
1c) How many molecules of product would be produced from 24.7g Na?
__________________________________________________________________________________
2a) In the reaction 2C8H18 + 25O2 --> 16CO2 + 18 H2O, the ratio of volumes of O2 to CO2
is _________________.
2b) If 27.3g of C8H18 are combusted, what mass of water will be produced?
2c) How many molecules of CO2 will be produced?
2d) How many atoms of H are in 2 mol of C8H18?
2e) What is the percentage, by mass, of the H in 2 mol of C8H18?
Friday, November 13, 2009
Homework 1
Balance the following equations:
1) ___ N2 + ___ F2 ___ NF3
2) ___ C6H10 + ___ O2 ___ CO2 + ___ H2O
3) ___ HBr + ___ KHCO3 ___ H2O + ___ KBr + ___ CO2
4) ___ GaBr3 + ___ Na2SO3 ___ Ga2(SO3)3 + ___ NaBr
5) ___ SnO + ___ NF3 ___ SnF2 + ___ N2O3
Using the equation from problem 2 above, answer the following questions:
6) If I do this reaction with 35 grams of C6H10 and 45 grams of oxygen, how many grams of carbon dioxide will be formed?
7) What is the limiting reagent for problem 6? ___________
8) How much of the excess reagent is left over after the reaction from problem 6 is finished?
9) If 35 grams of carbon dioxide are actually formed from the reaction in problem 6, what is the percent yield of this reaction?
1) ___ N2 + ___ F2 ___ NF3
2) ___ C6H10 + ___ O2 ___ CO2 + ___ H2O
3) ___ HBr + ___ KHCO3 ___ H2O + ___ KBr + ___ CO2
4) ___ GaBr3 + ___ Na2SO3 ___ Ga2(SO3)3 + ___ NaBr
5) ___ SnO + ___ NF3 ___ SnF2 + ___ N2O3
Using the equation from problem 2 above, answer the following questions:
6) If I do this reaction with 35 grams of C6H10 and 45 grams of oxygen, how many grams of carbon dioxide will be formed?
7) What is the limiting reagent for problem 6? ___________
8) How much of the excess reagent is left over after the reaction from problem 6 is finished?
9) If 35 grams of carbon dioxide are actually formed from the reaction in problem 6, what is the percent yield of this reaction?
Berllringer 2 and In Class Assignment 1
Bellringer 2
Calculate the number of grams of NaCl produced as a result of 62.4 gram of sodium reacting with chlorine. The balance equation is :
Na + Cl ---> NaCl
2. Molar calculations
3. In Class Assignment - Chapter 9, pg 262 #33-40.
Calculate the number of grams of NaCl produced as a result of 62.4 gram of sodium reacting with chlorine. The balance equation is :
Na + Cl ---> NaCl
2. Molar calculations
3. In Class Assignment - Chapter 9, pg 262 #33-40.
Third Six Weeks Begins/Bellringer 1
1. Bell Ringer
When 84.8 grams of iron (III) oxide reacts with an excess of carbon monoxide, 54.3 grams of iron is produced.
a. Write the equation for the reaction.
b. Balance the equation.
c. Calculate the mass of reactants and products.
d. Calculate the percent yield of this reaction.
2. All students will complete pages 81-85 (Sec 9.1-9.2) of AW Chemistry Workbook (found in the back glass cabinet). Turn in their work at the end of class in their period box.
When 84.8 grams of iron (III) oxide reacts with an excess of carbon monoxide, 54.3 grams of iron is produced.
a. Write the equation for the reaction.
b. Balance the equation.
c. Calculate the mass of reactants and products.
d. Calculate the percent yield of this reaction.
2. All students will complete pages 81-85 (Sec 9.1-9.2) of AW Chemistry Workbook (found in the back glass cabinet). Turn in their work at the end of class in their period box.
Dimension Analysis and Stoichiometry
http://www.slideshare.net/neubla/atoms-molecules-stoichometry-i
Slide presentation of the atomic mole, molar mass and atomic units.
Slide presentation of the atomic mole, molar mass and atomic units.
Tuesday, November 10, 2009
Monday, November 9, 2009
Waiver Day
No Students
You have a break to review for six weeks exam. Take the information that was given to you Friday and make sure you understand how to determine valence numbers, oxidation number, name compounds and balance equations.
You have a break to review for six weeks exam. Take the information that was given to you Friday and make sure you understand how to determine valence numbers, oxidation number, name compounds and balance equations.
Wednesday, November 4, 2009
Chemistry 2nd Six Weeks Review
Review includes notes, bellringers, labs and vocabulary.
More review can be found at
http://misterguch.brinkster.net/worksheets.html
More review can be found at
http://misterguch.brinkster.net/worksheets.html
Week of November 2-6 and November 9-13
Nov 2 Complete balancing equations
Nov 3-4 Lab 2: Conservation of Mass
Nov 5-6 Review for 2nd Six Weeks Exam
Nov 9 Waiver Day
Nov 10-11 Review for 2nd Six Weeks Exam
Nov 12-13 2nd Six Weeks Exam
Nov 3-4 Lab 2: Conservation of Mass
Nov 5-6 Review for 2nd Six Weeks Exam
Nov 9 Waiver Day
Nov 10-11 Review for 2nd Six Weeks Exam
Nov 12-13 2nd Six Weeks Exam
Subscribe to:
Posts (Atom)