Organic Chemistry, 7e by L. G. Wade, Jr. Chapter 1 Introduction and Review Christine Hermann Radford University Radford, VA Copyright © 2010 Pearson Education, Inc.

1.1 Define isotopes. a.Atoms with the same number of neutrons, but a different number of electrons. b.Atoms with the same number of protons, but a different number of electrons. c.Atoms with the same number of protons, but a different number of neutrons. d.Atoms with the same number of neutrons, but a different number of protons.

1.1 Answer a.Atoms with the same number of neutrons, but a different number of electrons. b.Atoms with the same number of protons, but a different number of electrons. c.Atoms with the same number of protons, but a different number of neutrons. d.Atoms with the same number of neutrons, but a different number of protons.

1.2 Describe the structure of an atom. a.Neutrons and protons are in the nucleus; electrons are in orbitals. b.Neutrons and electrons are in the nucleus; protons are in orbitals. c.Electrons and protons are in the nucleus; neutrons are in orbitals. d.Electrons are in the nucleus; neutrons and protons are in orbitals.

1.2 Answer a.Neutrons and protons are in the nucleus; electrons are in orbitals. b.Neutrons and electrons are in the nucleus; protons are in orbitals. c.Electrons and protons are in the nucleus; neutrons are in orbitals. d.Electrons are in the nucleus; neutrons and protons are in orbitals.

1.3 What is the electronic configuration for Al? a.1s 2 2s 2 2p 6 b.1s 2 2s 2 2p 6 3s 1 c.1s 2 2s 2 2p 6 3s 2 d.1s 2 2s 2 2p 6 3s 2 3p 1

1.3 Answer a.1s 2 2s 2 2p 6 b.1s 2 2s 2 2p 6 3s 1 c.1s 2 2s 2 2p 6 3s 2 d.1s 2 2s 2 2p 6 3s 2 3p 1

1.4 What is the electronic configuration for Ca +2 ? a.1s 2 2s 2 2p 6 3s 2 b.1s 2 2s 2 2p 6 3s 2 3p 6 c.1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 d.1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 4p 2

1.4 Answer a.1s 2 2s 2 2p 6 3s 2 b.1s 2 2s 2 2p 6 3s 2 3p 6 c.1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 d.1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 4p 2 Calcium has an electronic configuration of 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2. The +2 means the loss of the last two electrons.

1.5 Identify the compound with ionic bonding. a.CH 4 b.NaBr c.CH 3 Cl d.CH 3 OH

1.5 Answer a.CH 4 b.NaBr c.CH 3 Cl d.CH 3 OH Ionic bonds are formed between metals and nonmetals.

1.6 How many bonding pairs of electrons are in NH 2 OH? a.One pair of electrons b.Two pairs of electrons c.Three pairs of electrons d.Four pairs of electrons

1.6 Answer a.One pair of electrons b.Two pairs of electrons c.Three pairs of electrons d.Four pairs of electrons

1.7 How many nonbonding pairs of electrons are in NH 2 OH? a.One pair of electrons b.Two pairs of electrons c.Three pairs of electrons d.Four pairs of electrons

1.7 Answer a.One pair of electrons b.Two pairs of electrons c.Three pairs of electrons d.Four pairs of electrons NH 2 OH has one nonbonding pair on nitrogen and two nonbonding pairs on oxygen.

1.8 How many bonds (pairs of electrons) are in CH 2 =CH 2 ? a.Two bonds b.Three bonds c.Four bonds d.Five bonds e.Six bonds

1.8 Answer a.Two bonds b.Three bonds c.Four bonds d.Five bonds e.Six bonds CH 2  CH 2 has two carbon–carbon bonds and four single carbon– hydrogen bonds.

1.9 How does electronegativity change on the periodic table? a.Increase from left to right; increase from top to bottom. b.Increase from left to right; increase from bottom to top. c.Increase from right to left; increase from top to bottom. d.Increase from right to left; increase from bottom to top.

1.9 Answer a.Increase from left to right; increase from top to bottom. b.Increase from left to right; increase from bottom to top. c.Increase from right to left; increase from top to bottom. d.Increase from right to left; increase from bottom to top.

1.10 List the following atoms in decreasing electronegativity. a.C > Br > O > F b.F > O > C > Br c.F > O > Br > C d.F > C > O > Br

1.10 Answer a.C > Br > O > F b.F > O > C > Br c.F > O > Br > C d.F > C > O > Br

1.11 How many valence electrons does carbon have? a.Three valence electrons b.Four valence electrons c.Five valence electrons d.Six valence electrons e.Seven valence electrons

1.11 Answer a.Three valence electrons b.Four valence electrons c.Five valence electrons d.Six valence electrons e.Seven valence electrons Carbon has an electronic configuration of 1s 2 2s 2 2p 2 and thus, only has four electrons in its outer shell.

1.12 Identify the formal charge for C in CH a.-1 b.0 c.1 d.2

1.12 Answer a.-1 b.0 c.1 d.2

1.13 A compound has 85.72% carbon and 14.28% hydrogen. Give the empirical formula. a.CH b.CH 2 c.CH 3 d.CH 4

1.13 Answer a.CH b.CH 2 c.CH 3 d.CH 4

1.14 A compound has an EF of C 2 H 5 O and a MW of g/mole. What is the MF? a.C 3 H 10 O 2 b.C 4 H 8 O c.C 4 H 10 O 2 d.C 5 H 8 O e.C 6 H 10 O 2

1.14 Answer a.C 3 H 10 O 2 b.C 4 H 8 O c.C 4 H 10 O 2 d.C 5 H 8 O e.C 6 H 10 O 2 Empirical weight of C 2 H 5 O is g/mole / = 2. C 2x2 H 5x2 O = C 4 H 10 O 2

1.15 Identify the Arrhenius acid. HNO 3 + H 2 O  H 3 O + + NO 3 - a.HNO 3 b.H 2 O c.H 3 O + d.NO 3 -

1.15 Answer a.HNO 3 b.H 2 O c.H 3 O + d.NO 3 - HNO 3 dissociates in water to give H 3 O + (Arrhenius acid).

1.16 Identify the Brønsted–Lowry base. HCl + CH 3 NH 2  CH 3 NH Cl - a.HCl b.CH 3 NH 2 c.CH 3 NH 3 + d.Cl -

1.16 Answer a.HCl b.CH 3 NH 2 c.CH 3 NH 3 + d.Cl - CH 3 NH 2 is a species that can accept a proton (Brønsted-Lowry base).

1.17 Identify the Lewis base. CH 3 O - + CH 3 Br  CH 3 OCH 3 + Br - a.CH 3 O - b.CH 3 Br c.CH 3 OCH 3 d.Br -

1.17 Answer a.CH 3 O - b.CH 3 Br c.CH 3 OCH 3 d.Br - CH 3 O - is a species with nonbonding electrons that can be donated to form new bonds (Lewis base).

1.18 Identify the strongest acid. a.H 2 O b.CH 3 OH c.CH 3 COOH d.HF

1.18 Answer a.H 2 O b.CH 3 OH c.CH 3 COOH d.HF The acids decrease in strength in the order of HF > CH 3 COOH > CH 3 OH > H 2 O.

1.19 Identify the strongest base. a.NH 3 b.HCOO -1 c.CH 3 -1 d.OH -1

1.19 Answer a.NH 3 b.HCOO -1 c.CH 3 -1 d.OH -1 The bases decrease in strength in the order of CH 3 -1 > OH -1 > NH 3 > HCOO -1.

1.20 Define a nucleophile. a.A species that donates electrons. b.A species that accepts electrons. c.A species that accepts protons. d.A species that donates protons.

1.20 Answer a.A species that donates electrons. b.A species that accepts electrons. c.A species that accepts protons. d.A species that donates protons. A nucleophile donates electrons, and an electrophile accepts electrons.