Advanced Chemistry Bell Ringers - PowerPoint Presentation

Advanced Chemistry Bell Ringers

Bell Ringer Pick Up Your Copy of the Syllabus and briefly scan it. You will need to be ready to discuss 3 Q uestions OR Comments you have written down. At this time your Bell Ringer will be written on scratch paper or in the margin of your syllabus. You will not be turning them in for a grade but are expected to share our 3 items as part of class discussion.

Describe the classification of matter for water and for oxygen. You might find the image above helpful as well as the flow diagram on page 11 of your book.

Significant Digits/Figures Video https://www.youtube.com/watch?v=6oj4y0d44nQ

a. A. A chemical change B. Cannot determine without additional information C. Neither a physical nor a chemical change D. A physical change

b. A. A chemical change B. Cannot determine without additional information C. Neither a physical nor a chemical change D. A physical change

c. A. A chemical change B. Cannot determine without additional information C. Neither a physical nor a chemical change D. A physical change

Sample Exercise 1.3 Converting Units of Temperature ( a ) Using Equation 1.1, we have K = 31 + 273 = 304 K. ( b ) Using Equation 1.2, we have Solution A weather forecaster predicts the temperature will reach 31 ° C. What is this temperature ( a ) in K, ( b ) in ° F? Ethylene glycol, the major ingredient in antifreeze, freezes at -11.5 ° C. What is the freezing point in ( a ) K, ( b ) °F? Practice Exercise Solve the Practice Exercises You might reference the examples in the Solution Portion above.

How would the darts be positioned on the target for the case of “good accuracy, poor precision”? A. Scattered closely and average position is away from center. B. Scattered widely and average position is at the center. C. Scattered closely and average position is at the center. D. Scattered widely and average position is away from the center.

Sample Exercise 1.12 Conversions Involving Density Before we begin solving this exercise, we note the following: 1. We are given 1.00 gal of water (the known, or given, quantity) and asked to calculate its mass in grams (the unknown). 2. We have the following conversion factors either given, commonly known, or available on the back inside cover of the text: The first of these conversion factors must be used as written (with grams in the numerator) to give the desired result, whereas the last conversion factor must be inverted in order to cancel gallons: The unit of our final answer is appropriate, and we’ve taken care of our significant figures. We can further check our calculation by estimating. We can round 1.057 off to 1. Then focusing on the numbers that do not equal 1 gives 4 × 1000 = 4000 g, in agreement with the detailed calculation. Solution What is the mass in grams of 1.00 gal of water? The density of water is 1.00 g/mL. You will be solving the Practice Problem on the following slide. You have 3 minutes to copy this problem into your learning log for reference before we do our bell ringer practice problem.

Sample Exercise 1.12 Conversions Involving Density You should also use common sense to assess the reasonableness of your answer. In this case we know that most people can lift a gallon of milk with one hand, although it would be tiring to carry it around all day. Milk is mostly water and will have a density not too different from that of water. Therefore, we might estimate that a gallon of water has mass that is more than 5 lb but less than 50 lb. The mass we have calculated, 3.78 kg × 2.2 lb/kg = 8.3 lb, is thus reasonable as an order-of-magnitude estimate. Solution Continued The density of benzene is 0.879 g/mL. Calculate the mass in grams of 1.00 qt of benzene. Answer: 832 g Practice Exercise

Sample Exercise 1.5 Relating Significant Figures to the Uncertainty of a Measurement The value 4.0 has two significant figures, whereas 4.00 has three. This difference implies that the 4.0 has more uncertainty. A mass reported as 4.0 g indicates that the uncertainty is in the first decimal place. Thus, the mass might be anything between 3.9 and 4.1 g, which we can represent as 4.0 ± 0.1 g. A mass reported as 4.00 g indicates that the uncertainty is in the second decimal place. Thus, the mass might be anything between 3.99 and 4.01 g, which we can represent as 4.00 ± 0.01 g. (Without further information, we cannot be sure whether the difference in uncertainties of the two measurements reflects the precision or the accuracy of the measurement.) Solution What difference exists between the measured values 4.0 g and 4.00 g? A sample that has a mass of about 25 g is placed on a balance that has a precision of ± 0.001 g. How many significant figures should be reported for this measurement? Practice Exercise Below you have a Sample P roblem and then a Practice Problem to solve for your Bell R inger. Feel free to write the sample problem in your learning log as well.

Bell Ringer List 3 advantages and 3 disadvantages to True or False questioning…

Chapter 1 Quiz Chapter 1 Learning Logs are due…Place in the basket for grading Pick up your remotes and have out scratch paper/calculators if you feel you need them

Bell Ringer….Substitute Here. Did not use this Slide Alpha particles are Positively charged. Analyze the image at The right… What can you infer about the nucleus from the angles of interaction between an atom and an alpha particle?

Bell Ringer Carbon on the Periodic Table shows it has a mass of 12.011, but there is no such thing as a .011 of an atom. Explain how the average atomic masses (atomic weight) are found and how is that similar to finding your average test score in this class if you scored an 88%, 97%, 100% and 72%?

Bell Ringer Complete the chart below: Element # Protons # Neutrons # Electrons Mass # Ca20 40Li47N7 7 C-14 14 Cl -1 18 Al +3 14

Bell Ringer Butane is a four carbon hydrocarbon chain. Hydrocarbon means hydrogens and carbons. The ending – ane means only single bonds. Draw the structure for butane (Remember: Carbons like to form 4 bonds each). What is its molecular formula?What is its empirical formula?

Bell Ringer Copy the flow chart below into your Bell Ringer Notes. Then write out the name for CaCl 2 .

Experiment 2 Lab Day 1 of 3 Pick up the Lab Manuel at the front of the room. Open to page 29. Have your LAB Book out and b egin your log entry for the Table of Contents. Name 1 Period # Advanced Chemistry Lab Book Page ContentTable of Contents2-5 Experiment 1 6- Experiment 2

Lab Day 2 of 3 Data Collection Before you can begin collecting data…you must have your lab book entry preapproved. Procedures-short and sweet but shouldn’t need the manual to know how to do the lab. Safety section for chemicals and equipment we are using. Data/Observations (begin after approval)

Lab Day 3 of 3 We are in the library computer lab… Remember a full lab report includes: Intro , Procedures, Safety , Data & Observations , Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions.For this lab: Please submit typed Intro, Discussion of Results and Additional Questions to our turnitin.com account.No 3rd Person! Individual work!

Bell Ringer You have 3 minutes to list as many patterns that exist on the periodic table that you remember from the past. What does the period # mean? What does the group number mean? Atomic size? Atomic Charge? Number of protons or electrons?

Bell Ringer Pick up your chapter 2 study guide… Use a Green highlighter to mark any concepts you feel you know well.Use a Pink highlighter to mark any concepts you feel you need to study more before the exam.

Bell Ringer What is the molecular formula for pentane, the alkane with five carbons? What is the name and molecular formula for the alcohol derived from pentane?

Bell Ringer Copy and Complete the Chart Below into your Learning Log. Feel free to use Section 3.5 for reference if needed. Term What Particle Changes? Elemental Transmutation Electron Isotope Electron is LostAnion

Bell Ringer Draw a symbol to represent Single Displacement, Double Displacement, Synthesis, Decomposition and Combustion Reactions. Please remember that symbols do not generally contain numbers or letters.

Bell Ringer Write a balanced equation for the following problems… Zinc and lead (II) nitrate react to form zinc nitrate and lead . Aluminum and hydrochloric acid react to form aluminum chloride and hydrogen gas.

Bell Ringer Convert 0.200 moles of H 2 S to molecules and grams of sulfuric acid.

Bell Ringer Write a paragraph that describes step by step how to convert number of grams into number of atoms. Please remember the components of a good WAC paragraph…Organization, Content, Grammar and Critical Thinking.

Bell Ringer Honors Chem Flash Back…Don’t use the book unless you are absolutely stuck! Ascorbic Acid (Vitamin C) contains 40.92% C, 4.58% H and 54.50% O by mass. What is the empirical formula for ascorbic acid?

Bell Ringer Honors Chem Flash Back…Don’t use the book unless you are absolutely stuck !Determine how many grams of water are produced in the oxidation of 1.00 g of glucose, C6 H 12 O 6.

Bell Ringer Your Learning Log is Due October 23 rd (Thursday). You should have Chapter 3 completed. You have this class period to update any entries but BEFORE we do that…Flip back through your Log and find one question you have about the last 3 chapters. EVERYONE will share ONE question. Note: It doesn’t have to be a book question. It can be a general question about what we have learned.

Bell Ringer Day 1 of 3 for Experiment 3 Get your lab manual from the cabinet and begin writing up our Lab Log entry. Procedures…detailed by simplified Safety-MSDS is a good resource Data/Observation Table ready for collection IN PEN…Partners are fine to this point

Lab Day 2 of 3 Data Collection Before you can begin collecting data…you must have your lab book entry preapproved. Procedures-short and sweet but shouldn’t need the manual to know how to do the lab. Safety section for chemicals and equipment we are using. MSDS is your BFF. Data/Observations (begin after approval)

Lab Day 3 of 4 We are in the library computer lab FOR SURE TOMORROW!!! Remember a full lab report includes: Intro, Procedures, Safety , Data & Observations , Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions.You will be submitting all 8 sections to the turnitin.com account. No 3rd Person! Individual work!

Lab Day 4 of 4 In the computer lab… Remember a full lab report includes: Intro , Procedures, Safety , Data & Observations , Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions.You will be submitting all 8 sections to the turnitin.com account. No 3rd Person! Individual work!

Bell Ringer Solve the following nuclear reaction for the unknowns: A, Z and X 238 A 4 U  X + He Z 2 14 A 0 C  X + e6 Z -1

Bell Ringer Take out your phones or use school equipment to find Socrative …Follow the directions below to get logged into our Chapters 1-3 Review.

Chapters 1-3 Exam Pick up your remote from the CPS bag. Be sure that it is YOUR number. Begin testing immediately. You may use: Scratch paper and a NON-Programmable Calculator. No Cell Phones! GoodLuck#BigDay#StudyingIsGoodForU

Bell Ringer Solubility Mnemonics http :// www.youtube.com/watch?v=AsCLuLS-yZYMake your entry for 10/29/14 and be ready to copy the mnemonic for Solubility as your entry. We will be using this so take GOOD NOTES…

Bell Ringer Classify CaCl2, HNO3, C2H5OH, HCOOH, and KOH as a strong, weak or electrolyte…

Bell Ringer Classify CaCl 2 , HNO 3, C2H 5 OH, HCOOH, and KOH as a strong electrolyte, weak electrolyte or nonelectrolyte…All ionic compounds are strong electrolytes (see table 4.3) so they are strong. HNO3 is an acid therefore we classify it as strong (see table 4.2). HCOOH is a weak acid so it is a weak electrolyte. C2H5OH is not an acid or base so it is a nonelectrolyte.

Bell Ringer If we have Pb (NO 3)2, which of the following metals will be oxidized? You will need to refer to table 4.5 for Activity Series.Zn Cu Fe

Bell Ringer A reaction can occur with a metal if it is located above the reactant that is the meatal in its oxidized form. (see table 4.5). Zn-Yes Cu-No Fe-Yes

Bell Ringer How many grams of Na 2 SO 4 are required to make 0.350 L of 0.500 M Na2SO 4 ?

How many grams of Na 2 SO 4 are required to make 0.350 L of 0.500 M Na 2 SO 4 ? Sample Exercise 4.13 Using Molarity to Calculate Grams of Solute Analyze We are given the volume of the solution (0.350 L), its concentration (0.500 M ), and the identity of the solute Na 2 SO 4 and asked to calculate the number of grams of the solute in the solution. Plan We can use the definition of molarity (Equation 4.32) to determine the number of moles of solute, and thenconvert moles to grams using the molar mass of the solute. Solve Calculating the moles of Na2SO4 using the molarity and volume of solution gives Solution

Sample Exercise 4.13 Using Molarity to Calculate Grams of Solute Continued Because each mole of Na 2 SO 4 has a mass of 142 g, the required number of grams of Na 2 SO 4 is Check The magnitude of the answer, the units, and the number of significant figures are all appropriate. (a) How many grams of Na 2 SO 4 are there in 15 mL of 0.50 M Na 2 SO 4 ? (b) How many milliliters of 0.50 M Na2SO4 solution are needed to provide 0.038 mol of this salt?Answer: (a) 1.1 g, (b) 76 mL Practice Exercise

Bell Ringer FROM MEMORY What is our mnemonic for the 8 Solubility Rules? OR List the 8 Solubility Rules.

Bell Ringer What is our mnemonic for the 8 Solubility Rules? PMS * Nitrates NO3- Pb 2+ Acetates C 2 H3O2- Mercury Hg22+Group 1 Silver Ag+@*Sulfates SO42- Castro Bear @ Ammonium NH4+ Ca2+ *Group 17 Sr2+ Ba2+

Bell Ringer Day 1 of 3 for Group IA & Group IIA Cation Lab You will use a hand out to begin writing up our Lab Log entry. Procedures…detailed by simplified (should have prediction prior to starting) Safety-MSDS is a good resource Data/Observation Table ready for collection IN PEN…Partners are fine to this point

Lab Day 2 of 5 Data Collection Before you can begin collecting data…you must have your lab book entry preapproved. Procedures-short and sweet but shouldn’t need the manual to know how to do the lab. WITH A Prediction! Safety section for chemicals and equipment we are using. MSDS is your BFF. Data/Observations (begin after approval)

Lab Day 3 of 5 We are in the library computer lab Remember a full lab report includes: Intro , Procedures, Safety , Data & Observations , Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions.You will be submitting all 8 sections to the turnitin.com account. No 3rd Person! Individual work!

Lab Day 4 of 5 Unknown Identification Day! We are in the library computer lab tomorrow… Remember a full lab report includes: Intro, Procedures , Safety , Data & Observations, Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions. You will be submitting all 8 sections to the turnitin.com account.No 3rd Person! Individual work!

Lab Day 5 of 5 We are in the library computer lab Remember a full lab report includes: Intro , Procedures, Safety , Data & Observations , Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions.You will be submitting all 8 sections to the turnitin.com account. No 3rd Person! Individual work!

Bell Ringer Chapter 4 Quiz Today… Please have your remotes, scratch paper if you choose, Periodic Table and calculator ready!

Bell Ringer Considering the formula for work… W = f x d And considering the formula for Force… F = m x aWe use the unit Joule or J for energy. What is a J equal to if not using its short hand?

Bell Ringer If I told you in an experiment that a gas was compressed 910 kJ/ mol (the work) and the heat gained was -680 kJ/ mol, what would the change in E be?Hint: E = q + w

Bell Ringer w = -P V for a gas at STP H = E +PV H = (E +PV) H = E +PV assume P is constant Remember E = q + w and work associated with compressing a gas is w = -PVH = (qp + w) - w

Bell Ringer What to the roots mean for the following words? Exothermic Endothermic

Bell Ringer What to the roots mean for the following words? Exothermic - “to leave or outer” & “heat” Endothermic- “to enter or interior” & “heat”

Bell Ringer How much heat is released when 4.50 g of methane gas is burned in a constant-pressure system? ( Use the information given in Equation 5.18.)

Bell Ringer Our goal is to use a thermochemical equation to calculate the heat produced when a specific amount of methane gas is combusted. According to Equation 5.18, 890 kJ is released by the system when 1 mol CH 4 is burned at constant pressure. Equation 5.18 provides us with a stoichiometric conversion factor: (1mol CH 4 = 890 kJ). Thus, we can convert moles of CH 4 to kJ of energy. First, however, we must convert grams of CH4 to moles of CH4. Thus, the conversion sequence is grams CH 4 (given) → moles CH 4 → kJ (unknown to be found ). By adding the atomic weights of C and 4 H, we have 1 mol CH4 = 16.0 CH4. We can use the appropriate conversion factors to convert grams of CH4 to moles of CH4 to kilojoules: The negative sign indicates that the system released 250 kJ into the surroundings.

Bell Ringer The enthalpy of reaction for the combustion of C to CO 2 is –393.5 kJ/ mol C, and the enthalpy for the combustion of CO to CO2 is –283.0 kJ/mol C: Using these data, calculate the enthalpy for the combustion of C to CO:

Bell Ringer Solution

Bell Ringer Day 1 of 3 for Group IIIA & Group IVA & VA Cation Lab You will use a hand out to begin writing up our Lab Log entry. Procedures…detailed by simplified (should have prediction prior to starting) Safety-MSDS is a good resource Data/Observation Table ready for collection IN PEN…Partners are fine to this point

Lab Day 2 of 4 Data Collection Before you can begin collecting data…you must have your lab book entry preapproved. Procedures-short and sweet but shouldn’t need the manual to know how to do the lab. WITH A Prediction! Safety section for chemicals and equipment we are using. MSDS is your BFF. Data/Observations (begin after approval)

Lab Day 3 of 4 We are in the library computer lab Remember a full lab report includes: Intro , Procedures, Safety , Data & Observations , Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions.You will be submitting all 8 sections to the turnitin.com account. No 3rd Person! Individual work!

Bell Ringer The standard enthalpy change for the reaction CaCO 3 ( s) CaO(s) + CO2 ( g ) is 178.1 kJ. Use Table 5.3 to calculate the standard enthalpy of formation of CaCO3(s).Don’t Take Too LONG! Quiz Today over Chapter 5!

Bell Ringer Solution

Chapters 3-5 Exam Pick up your remote from the CPS bag. Be sure that it is YOUR number. Begin testing immediately. You may use: Scratch paper and a NON-Programmable Calculator. No Cell Phones!

Bell Ringer A light emits a light with a wave length 580 nm. What is the frequency (Hint for some of you that need it c = f x w…you know who you are). P.S. Another hint for those that need it…convert nm to meters.

Write a paragraph that describing the steps you would use in order to solve the following problem: Calculate the energy of one photon of yellow light that has a wavelength of 589 nm. Bell Ringer

Analyze Our task is to calculate the energy, E , of a photon, given λ = 589 nm. Plan We can use Equation 6.1 to convert the wavelength to frequency: v = c / λ We can then use Equation 6.3 to calculate energy: E = hvSolve The frequency, v, is calculated from the given wavelength, as shown in Sample Exercise 6.2: v = c/λ = 5.09 × 1014s-1 The value of Planck’s constant, h, is given both in the text and in the table of physical constants on the inside back cover of the text, and so we can easily calculate E: E = (6.626 × 10-34 J-s)(5.09 × 1014 s-1) = 3.37 × 10-19 JComment If one photon of radiant energy supplies 3.37 ×10-19 J, then one mole of these photons will supply (6.02 × 1023 photons/mol)(3.37 × 10-19J/photon) = 2.03 × 10 5J/mol Bell Ringer

Bell Ringer What is the wavelength of an electron moving with a speed of 5.97 × 10 6 m/s? The mass of the electron is 9.11 × 10 -31 kg.

Bell Ringer Analyze We are given the mass, m , and velocity, v , of the electron, and we must calculate its de Broglie wavelength , λ . Plan The wavelength of a moving particle is given by Equation 6.8, so λ is calculated by inserting the known quantities h, m, and v. In doing so, however, we must pay attention to units .Solve Using the value of Planck’s constant, h = 6.626 × 10-34 J-sWe have the following:  = h/(m)  = h/(m)  = (6.626 x 10 -34 js) x (1kgm2/s2) (9.11 x 10-31 kg) (5.97 x 106 m/s) 1 JComment By comparing this value with the wavelengths of electromagnetic radiation shown in Figure 6.4, we see that the wavelength of this electron is about the same as that of X-rays.

Bell Ringer Without referring to Table 6.2, a) predict the number of subshells in the fourth shell, that is, for n = 4. (b) Give the label for each of these subshells. ( c ) How many orbitals are in each of these subshells ? Hint: We are given the value of the principal quantum number, n. We need to determine the allowed values of l and ml for this given value of n and then count the number of orbitals in each subshell.

Bell Ringer There are four subshells in the fourth shell, corresponding to the four possible values of l (0, 1, 2, and 3). These subshells are labeled 4 s , 4 p , 4d, and 4f. The number given in the designation of a subshell is the principal quantum number, n; the letter designates the value of the angular momentum quantum number, l : for l = 0, s; for l = 1,p; for l = 2,d; for l = 3,f.There is one 4s orbital (when l = 0, there is only one possible value of ml: 0). There are three 4 p orbitals (when l = 1, there are three possible values of ml: 1, 0, -1 ). There are five 4 d orbitals (when 1 = 2 , there are five allowed values of m l: 2, 1, 0, -1, -2). There are seven 4f orbitals (when l = 3, there are seven permitted values of ml: 3, 2, 1, 0, -1, -2, -3).

Bell Ringer A student claims Phosphorus , element 15 has the electrons configuration 1 s22s2 2 p 6 3s23p2. Are the correct or false? Justify your answer.How many unpaired electrons does a phosphorus atom possess?

Bell Ringer Answers : ( a ) 1s22s22p 6 3 s 23p3, (b) three

Bell Ringer Mendeleev (& arguably Meyer) and Mosely both influenced the development of the modern Periodic Table. Who do you think is more responsible for what we use and why?

Bell Ringer Rank the following ions in order of increasing size (smallest to biggest). Cl - Ca2+S2-K +

Bell Ringer Rank the following ions in order of increasing size (smallest to biggest). Ca 2+ K+ Cl- S 2-

Bell Ringer Silicon has the electron configuration 1s 2 2s22p63s23p2 Is the following statement T/F and WHY? “The 2p electrons will be easier to remove then the 3p electrons because they are lower in energy level.”

Bell Ringer The electron affinity for Cl is -349 and -60 for Lithium. What is the relationship between ionization energy and the electron affinity? Don’t take forever because you are going to cut into your quiz time…

Chapters 6 & 7 Exam Pick up your remote from the CPS bag. Be sure that it is YOUR number. Begin testing immediately. You may use: Scratch paper and a NON-Programmable Calculator. No Cell Phones!

Bell Ringer Consider the lattice energies on page 293. What relationship is there between electronegativity and the lattice energy required to break the bonds?

Bell Ringer Draw the Lewis Dot structures for CO 2 and NH 3. Identify which one is a polar molecule and justify your answer. Page 299 has the electronegativity chart if you need assistance.

Bell Ringer Draw the Lewis Dot Structure for NO 3 - . What is a resonance structure and how does it impact your drawing?

Hint: We are asked to estimate the enthalpy change for a chemical reaction by using average bond enthalpies for the bonds broken and formed. In the reactants, we must break twelve C —H bonds and two C —C bonds in the two molecules of C 2 H 6 and seven O 2 bonds in the seven O 2 molecules. In the products, we form eight C==O bonds (two in each CO 2 ) and twelve O —H bonds (two in each H2O). Using data from Table 8.4, estimate H for the reaction

Using Equation 8.12 and data from Table 8.4, we have  H = [12 D (C—H) + 2 D (C—C) + 7 D (O 2 )] – [8 D (C==O) + 12 D (O —H)] = [12(413 kJ) + 2(348 kJ) + 7(495 kJ)] – [8(799 kJ) + 12(463 kJ)] = 9117 kJ – 11948 k J = –2831 kJ This estimate can be compared with the value of –2856 kJ calculated from more accurate thermochemical data meaning the estimate is reasonable.

Bell Ringer A single bond is usually longer than a double and a double bond usually has a longer bond length then a triple. What relationship would there be between single, double and triple bonds & the bond enthalpy associated with breaking those bonds?

Bell Ringer What do you have to know to determine a bond angle. Think geometry…You can’t have an angle if you don’t have __________.

Bell Ringer Draw the the molecular geometry for COCl 2 . Use this image to estimate the bond angles between the C-0 and the C-Cl bonds.

Bell Ringer Justify if you agree or disagree with the following statement: “SnCl 3 is a polar molecule.” Hint: Draw the molecular geometry and then use the electronegativities to determine if it has polarity.

Bell Ringer Justify if you agree or disagree with the following statement: “SnCl 3 is a polar molecule.”

Bell Ringer Justify if you agree or disagree with the following statement: “SnCl 3 is a polar molecule.”

HINT: To determine the central atom hybrid orbitals, we must know the electron-domain geometry around the atom. Thus, we draw the Lewis structure to determine the number of electron domains around the central atom. The hybridization conforms to the number and geometry of electron domains around the central atom as predicted by the VSEPR model. Bell Ringer Indicate the orbital hybridization around the central atom in NH 2 – .

Because there are four electron domains around N, the electron-domain geometry is tetrahedral. The hybridization that gives a tetrahedral electron-domain geometry is sp 3 (Table 9.4). Two of the sp 3 hybrid orbitals contain nonbonding pairs of electrons, and the other two are used to make bonds with the hydrogen atoms.

Bell Ringer

Why is it important that the sp 2 hybrid orbitals of the two carbon atoms lie in the same plane? A. To ensure that a sp 2 hybrid orbital on one carbon atom can bond to a sp 2 hybrid orbital on the other carbon atom or a hydrogen atom. B. To ensure that the H — C — H bond angle is 120 ° . C. To ensure that the unhybridized p orbitals on the carbon atoms are aligned properly to form a pi bond.D. To ensure that the H—C—C bond angle is 120°.

Hint: Single bonds σ are bonds, and double bonds consist of one π bond and one π bond. The ways in which these bonds form can be deduced from the molecular geometry, which we predict using the VSEPR model. Formaldehyde has the Lewis structure Describe how the bonds in formaldehyde are formed in terms of overlaps of hybrid and unhybridized oribitals . Bell Ringer

The O atom also has three electron domains around it, and so we assume it has sp 2 hybridization as well. One of these hybrid orbitals participates in the C — O σ bond, while the other two hold the two nonbonding electron pairs of the O atom. Like the C atom, therefore, the O atom has an unhybridized 2 p orbital that is perpendicular to the plane of the molecule. These two orbitals overlap to form a C — O π bond ( Figure 9.25) The C atom has three electron domains around it, which suggests a trigonal-planar geometry with bond angles of about 120 ° . This geometry implies sp 2 hybrid orbitals on C (Table 9.4). These hybrids are used to make the two C — H and one C — O bonds to C. There remains an unhybridized 2p orbital on carbon, perpendicular to the plane of the three sp2 hybrids.

Chapters 8 & 9 Exam Pick up your remote from the CPS bag. Be sure that it is YOUR number. Begin testing immediately. You may use: Scratch paper and a NON-Programmable Calculator. No Cell Phones!

Bell Ringer Day 1 of 4 for our Third Cation LabYou will use a hand out to begin writing up our Lab Log entry. Procedures…detailed by simplified (should have prediction prior to starting) Safety-MSDS is a good resource Data/Observation Table ready for collectionIN PEN…Partners are fine to this point

Lab Day 2 of 4 Data Collection Before you can begin collecting data…you must have your lab book entry preapproved. Procedures-short and sweet but shouldn’t need the manual to know how to do the lab. WITH A Prediction! Safety section for chemicals and equipment we are using. MSDS is your BFF. Data/Observations (begin after approval)

Lab Day 3 of 4 Unknown Day! May the force be with you and not the m x a kind… We are in the library computer lab TOMORROW! Remember a full lab report includes: Intro , Procedures, Safety, Data & Observations, Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions.You will be submitting all 8 sections to the turnitin.com account.No 3rd Person! Individual work!

Lab Day 4 of 4 We are in the library computer lab Remember a full lab report includes: Intro , Procedures , Safety, Data & Observations, Calculations & Results (excel graphs etc), Discussion of Results, References in ACS and Additional Questions. You will be submitting all 8 sections to the turnitin.com account.No 3rd Person! Individual work!

Bell Ringer ACS Practice for the Final Day…No time to play. Be seated and ready for instructions. Today’s Topic: Atomic Structure

Bell Ringer ACS Practice for the Final Day…No time to play. Be seated and ready for instructions. Today’s Topic: Molecular Structure and Bonding

Bell Ringer ACS Practice for the Final Day…No time to play. Be seated and ready for instructions. Today’s Topic: Stoichiometry

Bell Ringer ACS Practice for the Final Day…No time to play. Be seated and ready for instructions. Today’s Topic: States of Matter and Solutions

Bell Ringer ACS Practice for the Final Day…No time to play. Be seated and ready for instructions. Today’s Topic: Energetics

Finals Bell Ringer Pick up your remote, take out your calculator (no cell phones) & scratch paper. No personal periodic tables but the one in our test booklet or on the wall is fair game. Your grade is based on number correct so it is to your best interest to answer every question.