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1.5: Solutions to Chapter 1 Exercises

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    a) The atomic number of P (phosphorus) is 15, meaning there are 15 protons. The mass number for the 31P isotope is 31, so:

    15 protons + 16 neutrons = mass number 31

    (recall that mass number is number of protons and neutrons).

    (for parts b-d, use the same reasoning as above)

    b) 15 protons + 17 neutrons = mass number 32

    c) 17 protons + 20 neutrons = mass number 37

    d) 1 proton + 2 neutrons = mass number 3

    e) 6 protons + 8 neutrons = mass number 14


    a) 1s22s22p3

    b) 1s22s22p4

    c) 1s22s22p5

    d) 1s22s22p63s2

    e) 1s22s22p6 (same as Neon atom)

    f) 1s22s22p63s23p64s1

    g) 1s22s22p63s23p6 (same as Argon atom)

    h) 1s22s22p63s23p6 (same as Argon atom)

    i) 1s22s22p63s23p4

    j) 1s2 (same as Helium atom)

    k) 1s22s22p63s23p6 (same as Argon atom)




    E1.6: Below are full structural drawings, showing all carbons and hydrogens:


    E1.10: There is only one constitutional isomer of ethanol: dimethyl ether CH3OCH3



    a) carboxylate, sulfide, aromatic, two amide groups (one of which is cyclic)

    b) tertiary alcohol, thioester

    c) carboxylate, ketone

    d) ether, primary amine, alkene


    acetic acid: ethanoic acid

    chloroform: trichloromethane

    acetone: propanone (not 2-propanone, because the '2' in this case would be redundant: if the carbonyl carbon were not in the #2 position, the compound would be an aldehyde not a ketone)

    E1.17: The linking group is a phosphate diester