Ch. 1 - A Review of General ChemistrySee all chapters
All Chapters
Ch. 1 - A Review of General Chemistry
Ch. 2 - Molecular Representations
Ch. 3 - Acids and Bases
Ch. 4 - Alkanes and Cycloalkanes
Ch. 5 - Chirality
Ch. 6 - Thermodynamics and Kinetics
Ch. 7 - Substitution Reactions
Ch. 8 - Elimination Reactions
Ch. 9 - Alkenes and Alkynes
Ch. 10 - Addition Reactions
Ch. 11 - Radical Reactions
Ch. 12 - Alcohols, Ethers, Epoxides and Thiols
Ch. 13 - Alcohols and Carbonyl Compounds
Ch. 14 - Synthetic Techniques
Ch. 15 - Analytical Techniques: IR, NMR, Mass Spect
Ch. 16 - Conjugated Systems
Ch. 17 - Aromaticity
Ch. 18 - Reactions of Aromatics: EAS and Beyond
Ch. 19 - Aldehydes and Ketones: Nucleophilic Addition
Ch. 20 - Carboxylic Acid Derivatives: NAS
Ch. 21 - Enolate Chemistry: Reactions at the Alpha-Carbon
Ch. 22 - Condensation Chemistry
Ch. 23 - Amines
Ch. 24 - Carbohydrates
Ch. 25 - Phenols
Ch. 26 - Amino Acids, Peptides, and Proteins

Aufbau Principle predicts that carbon would have two partially filled 2p orbitals, suggesting that carbon could only make 2 bonds. However, carbon actually makes 4 bonds.

How do we explain this?  

Carbon Excites an Electron

Concept #1: How carbon creates 4 partially-filled orbitals. 

In terms of stability, now we have fewer filled orbitals, AND we had to excite an electron to do it.  Why is it better to have 4 partially-filled orbitals? 

Carbon Hybridizes Orbitals

Concept #2: How carbon makes 4 sp3 orbitals. 

Carbon “blends” its 2s orbital with the 2px, 2py and 2pz orbitals to create 4 new hybridized orbitals of equal energy.  These are called 2sp3 orbitals or simply “sp3” orbitals. 

Predicting Hybridization for Other Atoms

Concept #3: Using bond sites to predict hybridization  

A bond site is the name that we give to any lone pair or atom attached to the hybridized atom. The number of bond sites is what determines the hybridization of the molecule (see above picture). 

Hybridization of Reactive Intermediates

Concept #4: Introduction to the reactive intermediates. 

Example #1: Predict the number of bond sites, hybridization, and intermediate orbitals of the above reactive intermediates.   

So I know that was a loaded topic! If you found the part of intermediate orbitals a little confusing, that’s honestly fine as long as you know how to count bond sites and predict hybridization (will definitely show up on your exam). 

Additional Problems
For the following molecule, write the hybridization state of each atom indicated by the arrow.
Which statement below is FALSE? A. The C-H bond in an alkane that arises from  sp3-s overlap is  weaker than the C-H bond in an  alkyne that arises from sp-s overlap. B. The carbon-carbon  triple bond in an  alkyne is shorter than the carbon-carbon double bond in an alkene. C. The carbon-carbon triple bond in an alkyne is exactly three times as strong as the carbon-carbon single bond in an alkane. D. The C-H bond in an alkane that arises from  sp3-s overlap is longer than the C-H bond in an alkyne that arises from sp-s overlap. E. None of the above.
Indicate the hybridization for carbon a,b,c and d. a. ____________             b. _____________ c. ____________              d. _____________
Answer the following questions based on the structure shown below. What orbitals are involved in each of the labeled bonds?
What is the hybridization of each of the carbon and oxygen atoms in the following compound? 
Answer the following questions based on the structure shown below. What orbitals are involved in each of the labeled bonds?
Describe each bond indicated with an arrow as the overlap of orbitals. For example, an answer might be σ Csp3-Csp3. 
What is the hybridization of the orbital containing the unshared pair of electrons on the nitrogen atom in pyridine? a) s b) sp c) sp2 d) sp3
What are the hybridization of the atoms marked I, II, III, and IV in the molecule?
Each oxygen atom not bonded directly to hydrogen in HCO 3 – uses the same kind of hybrid orbital to form a sigma bond to the central carbon atom. What type of hybrid orbital is used by these oxygen atoms to form these sigma bonds? A. sp B. sp2 C. sp3
Identify whether there are more or less 1s-sp  3 bonds than 1s-sp 2 bonds in the following molecule. Are they shorter or longer than the 1s-sp 2 bonds? a. More 1s-sp 3 bonds; shorter b. More 1s-sp 3 bonds; longer c. Less 1s-sp 3 bonds; shorter d. Less 1s-sp 3 bonds; longer e. Equal number of 1s-sp 2 and 1s-sp 3; equal lengths
The radical in the following molecules is in what type of orbital? a. sp3 b. sp2 c. sp d. s e. p
Which statement best describes the orbitals that are used to form the bonds on the allylic carbon below? a. The π bond between the two carbon atoms is formed by the overlap of two sp  2 hybridized bonding orbitals. b. The lone pair rests in a non-bonding sp 2 hybridized orbital. c. The σ bond between the oxygen and the carbon is formed by the overlap of two sp  3 hybridized bonding orbitals.  d. The σ bond between the carbon and the hydrogen is formed by the overlap of a 1s orbital and a non-bonding sp 2 hybridized orbital. e. None of the statements are true. 
Indicate the number of hydrogen atom(s) on each carbon atom of the following molecule and give the hybridization of each carbon atom.   
Predict the sigma bond hybridizations indicated by the arrows in the following molecule.  
Identify the atomic orbitals in the noted C-N sigma bond in the following molecule a) 2sp2, 2sp2 b) 2sp3, 2sp3 c) 2sp, 2sp d) 2p, 2p
What kinds of orbitals overlap to form the σ bond found in the single bond marked with the label 29 in the structure of Lamisil shown below?   A. sp 3–sp 3            C. sp–sp               E. sp   3–sp          G. sp  3–p           I. sp–p B. sp  2–sp  2           D. s p 3–sp 2         F. sp 2–sp           H. sp  2–p           J. p–p
What kinds of orbitals overlap to form the π bond found in the double bond marked with the label 30 in the structure of Lamisil shown above?   A. sp 3–sp 3           C. sp –sp           E. sp  3–sp          G. sp 3–p            I. sp–p B. sp 2–sp  2           D. sp 3–sp 2         F. sp 2–sp           H. sp 2–p           J. p–p  
What is the total number of unhybridized p-orbitals present in the following molecule? 
The reaction shown is important in the industrial preparation of dichlorodimethylsilane for eventual conversion to silicone polymers. 2CH3Cl + Cl + Si → (CH 3)2SiCl2 (b) On the basis of the molecular model of (CH 3)2SiCl2, deduce the hybridization state of silicon in this compound. What is the principal quantum number n of the silicon s and p orbitals that are hybridized?
Each of the indicated bonds is a result of the overlapping of orbitals. What are they?  
What is the hybridization of oxygen or nitrogen in each of the following?  
What is the hybridization of oxygen or nitrogen in each of the following?
What is the hybridization of oxygen or nitrogen in each of the following?
What is the hybridization of oxygen or nitrogen in each of the following?  
What is the hybridization of oxygen or nitrogen in each of the following?
Consider the structure given below. All lone pairs and non-zero formal charges are shown explicitly in this structure. What is the hybridization of the carbon atom marked with the arrow? A. sp          B. sp 2           C. sp 3
Identify the hybridization state and geometry of each carbon atom in the following compounds: 
Describe each bond indicated with an arrow as the overlap of orbitals. For example an answer might be σCsp3 -Csp3
What are the hybridizations of the atoms (1 and 2, respectively in the following structure? A) sp3 and sp2  B) sp2 and sp2 C) sp2 and sp3 D) sp and sp2 E) sp3 and sp
On the lines provided, state the hybridization state of the atom indicated by the arrow.
Ramelteon is a hypnotic agent used in the treatment of insomnia:  (d)  How many sp-hybridized carbon atoms are present in this structure? 
Ramelteon is a hypnotic agent used in the treatment of insomnia:  (c)  How many sp2-hybridized carbon atoms are present in this structure? 
Ramelteon is a hypnotic agent used in the treatment of insomnia:  (b)  How many sp3-hybridized carbon atoms are present in this structure? 
Cycloserine is an antibiotic isolated from the microbe Streptomyces orchidaceous. It is used in conjunction with other drugs for the treatment of tuberculosis.  (b)  How many sp3-hybridized carbon atoms are present in this structure? 
Cycloserine is an antibiotic isolated from the microbe Streptomyces orchidaceous. It is used in conjunction with other drugs for the treatment of tuberculosis.  (c)  How many sp2-hybridized carbon atoms are present in this structure? 
Cycloserine is an antibiotic isolated from the microbe Streptomyces orchidaceous. It is used in conjunction with other drugs for the treatment of tuberculosis.  (d)  How many sp-hybridized carbon atoms are present in this structure? 
Draw a three-dimensional orbital representation for each of the following molecules, indicate whether each bond in it is a σ or π  bond, and provide the hybridization for each non-hydrogen atom. (a) CH2O
Draw a three-dimensional orbital representation for each of the following molecules, indicate whether each bond in it is a σ or π  bond, and provide the hybridization for each non-hydrogen atom.
Draw a three-dimensional orbital representation for each of the following molecules, indicate whether each bond in it is a σ or π  bond, and provide the hybridization for each non-hydrogen atom.
Write the hybridization of each of the indicated atom in the box provided.
Look at the  entire structure of Atenolol. What is the  total number of sigma (σ) bonds present within the structure that are formed as a result of overlap of an sp 2  orbital on one atom with an sp3  orbital on the adjacent atom? A. 0 B. 1 C. 2 D. 3 E. 4 F. 5 G. 6 H. 7 I.  8 J. None of these
The number of chemical bonds between two atoms is described by the  bond order. For example, a single bond has a bond order of 1, and a triple bond has a bond order of 3. In a resonance hybrid, the bond order need not be an integer quantity! Look at the carbon-carbon bond labeled  38 in the structure of atenolol above. What is the  bond order of this carbon-carbon bond? Pick the  one choice below which best answers this question. A. 0.5 B. 1.0 C. 1.5 D. 2.0 E. 2.5 F. 3.0 G. None of these
The structure of Cyclosporin is given below. Cyclosporin is a cyclic peptide prescribed to the patients to lower the body's immune system (it is known as immunosuppressant).Give the hybridization of the P, Q and R atoms indicated by the arrows:a) P-sp3, Q-sp3, R-sp2b) P-sp3, Q-sp2, R-sp3c) P-sp2, Q-sp2, R-sp3d) P-sp2, Q-sp3, R-sp3How many Pi bonds does this molecule have?a) 10b) 11c) 12d) 13
(a) Consider a carbon atom in its ground state. Would such an atom offer a satisfactory model for the carbon of methane? If not, why not? (Hint: Consider whether a ground state carbon atom could be tetravalent, and consider the bond angles that would result if it were to combine with hydrogen atoms.)
Propose at least two different structures for a compound with six carbon atoms that exhibits the following features:(b) Only one carbon atom is sp hybridized, and the remaining ve carbon atoms are all sp3 hybridized (remember that your compound can have elements other than carbon and hydrogen).
Give examples of hydrocarbon molecules that consist of just one carbon atom and which typify each of the four types of reactive organic intermediates. Include the names of the intermediates.Determine the formal charge and hybridization of each of the intermediates above.
What kind of orbital does the positive charge in a methyl cation rest in?
What kind of orbital does the lone pair in a carbene rest in?
List the type and quantity of the orbitals for each of the three hybridization states of carbon. 
In which orbitals the lone pair of electrons of the nitrogen atom in the following compound is located? A. sp3B. sp2C. spD. sE. p
Hybridization for CH2 = _____________ Hybridization for C≡N = _____________ Drag and drop your selection from the following list to complete the answer: sp2              sp             sp  3
Nicotine is an addictive substance found in tobacco. Identify the hybridization state and geometry of each of the nitrogen atoms in nicotine: Use the following values to indicate hybridization state: 1 = sp; 2 = sp2; 3 = sp3. Nitrogen 1 is ________ hybridized and  ________. Nitrogen 2 is _________ hybridized and  ________.
Which bond is formed from the interaction of an sp3 hybridized orbital with an sp hybridized orbital?
What type(s) of orbital overlap is(are) used to form the indicated bond in the following structure. (i) sp2-sp2 (ii) p-p orbitals (iii) sp3-sp3 (iv) sp2-s (v) sp2-sp2 (vi) sp2-s 
Which atomic orbitals overlap to form the C=O sigma bond of acetone, (CH3)2C=O? a. C 2sp2 + O 2p b. C 2sp3 + O 2sp c. C 2sp3 + O 2sp2 d. C sp2 + O 2sp2 
Consider the following structure and answer the questions below:a. The number of sigma bonds is:b. The number of pi bonds is:c. The state of hybridization of C in the C=O bond (either one) is: 
What is the molecular geometry around the methyl carbons (CH3) atom in the drawing below? (A) Linear (B) Bent (C) Trigonal planar (D) Trigonal pyramidal (E) Tetrahedral
Based on the structure below, what is the value for the H-N-CH3 bond angle? 
Which atoms are sp2 hybridized? Select the appropriate atoms by clicking them. 
What type(s) of orbital overlap is(are) used to form the indicated bond in the following structure.
How many δ and π bonds are in this molecule? 
For question below use the Lewis structure for acetic acid shown here. The ideal value for the H-C-H bond angle about atom 1 is: a. 120° b. 60°c. 109.5°d. 90°e. 180°
What type(s) of orbital overlap is (are) used to form the indicated bond in the following structure. a. sp3 -s b. sp3 - sp3 c. p-p orbitals d. sp2 - s e. sp2 - sp2 f. sp3 - sp2
In a double-bonded carbon atom:a. no hybridization occurs between the s and p orbitalsb. hybridization occurs between the s orbital and three p orbitalsc. hybridization occurs between the s orbital and one p orbitald. hybridization occurs between the s orbital and two p orbitals. 
The four C-C single bonds are labeled in this compound. Which of these is the shortest bond?
Show the kinds of orbitals that overlap to form each bond for HC≡C-CHO.Drag the appropriate labels to their respective targets. Note: not all labels will be used.
There are__sp3 hybridized atoms in the following compound. CH_3CH_2CH_2CHCH_2 a. hree b. fourc. five d. two
What hybrid orbitals make up the indicated bond in the organic compound?
What is the hybridization of nitrogen in the following molecules? (Type your answer using the format sp2.)HNNHH3CNCH3CNH2