Chem 104 1st exam|Complete Questions with 100% Correct Answers

Chem 104 1st exam|Complete Questions with 100% Correct Answers What are hybrid orbitals? orbitals of equal energy produced by the combination of two or more orbitals on the same atom What are the types of hybrid orbitals SP- 2 regions of density SP^2- 3 regions of density(3sp^2s) SP^3- 4 regions (4 sp^3s) What are the 4 types of hydrocarbons alkanes, alkenes, alkynes, and aromatic hydrocarbons Alkane a hydrocarbon containing only single covalent bonds Alkene a hydrocarbon that contains one or more double bond between a carbon Alkyne a hydrocarbon that contains one or more triple bond (between carbons) aromatic carbon ring What are the hydrocarbon prefixes 1 C- methane (CH4) 2C- ethane (C2H6) 3c- Propane 4C- butane 5C pentane 6C hexane 7C heptane 8C octane 9C nonane 10C decane Methyl CH3- Ethyl CH3CH2- Propyl CH3CH2CH2- Butyl CH3CH2CH2CH2- isopropyl CH3CHCH3- Isomers Two different molecules that have the same chemical formula structural (constitutional) isomers same molecular formula, different connectivity How can you convert one structural isomer to another Break and rejoin the atoms When you have greater surface area what does that indicate about LDF Greater surface area=greater LDF Greater IMFs produce — boiling points Greater What are the 3 parts to a compounds name Prefix|base|suffix What substituents|how many C|family How to name hydrocarbons longest continuous carbon chain. This is your base. r the chain from end nearest the 1st substituent encountered substituent as a prefix along with numbers of carbons to which they're attached there are more than 1 type of substituents in the molecule, list them alphabetically presence of 2 or more of the same substituent is indicated by prefix (di, tri, tetra, penta, hexa) Hydrocarbons the simplest organic compounds, composed of only carbon and hydrogen In alkanes what hybridization does carbon have SP^3 noncyclic alkanes all have a formula of C(n)H(2n+2) Nomenclature Set of rules to allow for systematic and consistent naming of compounds Nomenclature has 2 rules for naming alkanes identify the longest chain of carbon atoms in its structure (1:meth, 2:eth, 3:prop, 4: but, 5:pent, 6: hex,7:hept, 8:oct, 9:non,10:dec) prefixes to the name of the longest chain to indicate positions and name of substituents What happens if more than 1 type of substituent is present When more than one substituent is present either on the same carbon atom or on different atoms the substituents are listed alphabetically How do you name an electronegative substituent The ending o replaces -ide at end of naming en substituent An ionic compounds the negatively charged ion ends with — in organic compounds. Such adults are treated as substituents and ending — is used Ide O Because the carbon atom numbering begins at the end closest to a substituent. The longest change of carbon atoms is numbered how? In such a way to produce the lowest numbers for substituents How would you indicate the number number of substituents of the same type? By using prefixes di, tri, tetra, penta, etc alkyl group An alkane with a hydrogen atom removed, e.g. CH3, C2H5; alkyl groups are often shown as 'R'. tert-butyl -C(CH3)3 Do alkyl groups exist as stable independent entities No When do unbranched chains exist When no carbon atom is bonded to no more than 2 other carbons How do you often name unbranched chains Begin with the term normal or n- How do you predict all isomers Begin with longest C chain 2. Remove one carbon from the longest chain and find unique locations where a CH3 group may be added to the remaining carbon chain. 3. Repeat, removing an additional carbons from the longest chain and then distribute the carbon to unique locations to form more isomers What IMFs are in alkanes LDFs because alkanes only have LDFs they have relatively low, melting points and boiling points, and they have low solubility in polar solvents like water As more mass of the molecules increase the strength of the dispersion forces Increase Increasing the potential surface contact between molecules — dispersion forces so longer carbon chains will have — dispersion forces Increases Greater Different isomers of outcomes with the same chemical formula may also exhibit different strength of dispersion forces. The less branch an isomer is, the — surface area on the molecule will have to interact with other molecules leading to — dispersion forces Greater Stronger Cycloalkanes Cyclic alkanes where the carbon atoms are connected in a ring What is the general formula for cycloalkanes? CnH2n How do you name cycloalkanes the same as alkanes but placing cyclo in front of the word Unsaturated Organic compounds that contain one or more double or triple bond between carbon atoms alkenes Unsaturated hydrocarbon molecules that contain one or more double bond Geometric isomer Adam's are attached in the same order but the spatial arrangement differs. In order for it to be a geometric isomer each carbon of the carbon carbon bond must have two different groups attached to it. Carbon atoms are free to rotate around a single bond, but what about double bonds? Corbin Adams cannot rotate her on double bonds due to them being rigid Is it possible to have two Iser of 2 - butane Yes, because you can have both methyl groups on the same side of the double bond(cis) or the methyl groups on the opposite sides(trans) The less branch, an isomer is the greater the surface area along the molecule will have to interact with other molecules. What does this lead to? Stronger, dispersion forces, greater boiling points, and greater melting points If you have polar bonds, in cis and trans isomers which one is typically more polar Cis optical isomers Have the same molecular formula and connectivity but are mirror images of each other, and not superimposable. They have at least 1 chiral carbon chiral A molecule or carbon atom bonded to four different groups and without a plane of symmetry(sp^3); thus, it is not superimposable upon its mirror image and has an enantiomer. Do optical isomers share boiling and melting points Yes Is it possible to separate optical isomers Yes but requires equipment we don't have Alkane single bond General Alkane Formula C(n)H(2n+2) Alkene C=C CnH2n Alkyne formula 1 carbon-carbon triple bond CnH2n-2 (triple bond) Cycloalkanes formula CnH2n aromatic hydrocarbons hydrocarbons that contain similar ring structures Cycloalkanes alkanes in which the carbon atoms are arranged in a ring, or cyclic, structure What cycloalkane is the most stable? Five and six membered rings are most stable because the angles are close to tetrahedral angles Are three or four membered rings, able to have tetrahedral angles No, because the orbital overlap is an ideal Unsaturated Contains less hydrogen than alkane with the same number of carbon atoms Is it possible to rotate around a double carbon bond? No, because it requires breaking a pie bond. What hybridizations are always locked SP2 and SP How do you name alkenes The suffix -ene is added to the base name, and then the chain is numbered so the carbon-carbon double bond the smallest possible number Geometric isomer They have restricted rotation around the carbon-carbon double bonds, or the cycloalkane carbon carbon bonds and as a result, you get molecules with the same connectivity, but different 3-D shapes and properties Cisisomer Have carbons in the chain on the same side of the molecule Transisomers Have carbons in the chain on opposite sides of the molecule What do you need in order to have a geometric isomer?