Problems for chapter 11

Learning Check Identify each of the following characteristics as most typical of compounds that are inorganic or organic. ___ 1. has a high melting point ___ 2. is not soluble in water ___ 3. has a formula CH3─CH2─CH3 ___ 4. has a formula MgCl2 ___ 5. is flammable ___ 6. is nonpolar

Solution Identify each of the following characteristics as most typical of compounds that are inorganic or organic. inorganic 1. has a high melting point organic 2. is not soluble in water organic 3. has a formula CH3─CH2─CH3 inorganic 4. has a formula MgCl2 organic 5. is flammable organic 6. is nonpolar

Learning Check Identify each of the following molecules as organic or inorganic. A. C3H8 B. C7H14Cl2 C. CaCl2 D. CH3OH E. SiH4

Solution Identify each of the following molecules as organic or inorganic. A. C3H8 B. C7H14Cl2 C. CaCl2 D. CH3OH E. SiH4 organic inorganic

Learning Check 1. Give the name of each of the following compounds. A. CH3—CH3 B. CH3—CH2—CH3 C. CH3—CH2—CH2—CH2—CH2—CH3 2. Write the condensed structural formula of pentane.

Solution 1. Give the name of each of the following compounds. A. CH3—CH3 ethane B. CH3—CH2—CH3 propane C. CH3—CH2—CH2—CH2—CH2—CH3 hexane 2. Write the condensed structural formula of pentane. CH3—CH2—CH2—CH2—CH3

Learning Check 1. Draw the condensed structural formula of A. What is its molecular formula? B. What is its name?

Learning Check 1. Draw the condensed structural formula of A. What is its molecular formula? C6H14 B. What is its name? hexane

Learning Check Draw the condensed structural formula for the following alkanes. A. ethane B. heptane

Solution Draw the condensed structural formula for the following alkanes. A. ethane B. heptane CH3─CH3 CH3─CH2─CH2─CH2─CH2─CH2─CH3

Learning Check The molecule testosterone contains five carbon rings. Answer the following questions about the molecule. Name each of the cycloalkanes that can be found in this molecule.

Solution The molecule testosterone contains five carbon rings. Answer the following questions about the molecule. Name each of the cycloalkanes that can be found in this molecule. cyclohexane cyclopentane

Learning Check Name the following alkanes. A. CH3─CH2─CH2─CH3 B. C. CH3─CH2─CH2─CH2─CH2─CH2─CH2─CH3 D.

Learning Check Name the following alkanes. A. CH3─CH2─CH2─CH3 B. C. CH3─CH2─CH2─CH2─CH2─CH2─CH2─CH3 D. butane cyclobutane octane cyclohexane 15

Learning Check Identify each pair of condensed structural formulas as structural isomers or the same molecule. A. B. C. 16

Solution Identify each pair of condensed structural formulas as structural isomers or the same molecule. A. structural isomers structural isomers B. C. same molecule 17

Learning Check What is the alkane name of the following? 18

Solution What is the alkane name of the following? Step 1 Write the alkane name of the longest chain of carbon atoms. 4 C's = butane Step 2 Number the carbon atoms starting from the end nearer a substituent. 19

Solution What is the alkane name of the following? Step 3 Give the location and name of each substituent (alphabetical order) as a prefix to the name of the main chain. 2-methylbutane 20

Learning Check What is the IUPAC name for the following? 21

Solution What is the IUPAC name for the following? Step 1 Write the alkane name of the longest chain of carbon atoms. 5 C's = pentane Step 2 Number the carbon atoms starting from the end nearer a substituent. 22

Solution What is the IUPAC name for the following? Step 3 Give the location and name of each substituent (alphabetical order) as a prefix to the name of the main chain. 3-chloro-2-methylpentane 23

Learning Check Give the IUPAC name for each of the following. 24

Solution 2,4-dimethylhexane 1 2 3 4 5 6 7 6 5 4 3 2 1 more substituents on C3 7 6 5 4 3 2 1 3,5-dichloro-3-methylheptane 25

Learning Check Draw the condensed structural formula for 3-bromo-1-chlorobutane. 26

Solution Draw the condensed structural formula for 3-bromo-1-chlorobutane. Step 1 Draw the main chain of carbon atoms. C─C─C─C Step 2 Number the chain and place the substituents on the carbons indicated by the numbers. 27

Solution Draw the condensed structural formula for 3-bromo-1-chlorobutane. Step 3 Add the correct number of hydrogen atoms to give four bonds to each C atom. 28

Learning Check Name each of the following: 29

Solution Name each of the following: methylcyclopropane 3-chloro-1-ethylcyclohexane 30

Learning Check Write three isomers of C5H12, and name each. 31

Solution A chain of 5 carbon atoms CH3─CH2─CH2─CH2─CH3 pentane A chain of 4 carbon atoms and 1 carbon branch 2-methylbutane A chain of 3 carbon atoms and 2 carbon branches 2,2-dimethylpropane 32

Learning Check For the following pairs of hydrocarbons, which one has the higher boiling point? Why? 1. Butane or octane 2. Hexane or 2,3-dimethylbutane

Solution For the following pairs of hydrocarbons, which one has the higher boiling point? Why? 1. Butane or octane Octane (has more carbon atoms) and, therefore, a higher boiling point. 2. Hexane or 2,3-dimethylbutane Both alkanes have the same number of carbon atoms. Hexane is not branched and, therefore, has the higher boiling point.

Learning Check Propane gas is used to provide heat for cooking. Write a balanced equation for the combustion of propane.

Solution Propane gas is used to provide heat for cooking. Write a balanced equation for the combustion of propane. Unbalanced equation: Balance C: Balance H: Balance O: To balance the atoms in the formula C3H8, we place a coefficient of 3 in front of CO2 and a coefficient of 4 in front of H2O. The total O in the products is 10 O (6 O in 3CO2 and 4 O in 4 H2O). To balance the 10 O, a coefficient of 5 is placed in front of the O2.

Learning Check Write a balanced equation for the reaction for the complete combustion of heptane, C7H16.

Solution Write a balanced equation for the reaction for the complete combustion of heptane, C7H16. Balanced equation:

Learning Check Classify each of the following as alcohol, ether, aldehyde, ketone, carboxylic acid, ester, or amine. A. B. C. D. E. 39

Learning Check Classify each of the following as alcohol, ether, aldehyde, ketone, carboxylic acid, ester, or amine. A. B. C. D. E. alcohol ether amine carboxylic acid ester 40