Section Outline Section 2 1 2 1 The

Section Outline Section 2 -1 • 2– 1 The Nature of Matter A. Atoms B. Elements and Isotopes 1. Isotopes 2. Radioactive Isotopes C. Chemical Compounds D. Chemical Bonds 1. Ionic Bonds 2. Covalent Bonds 3. Van der Waals Forces Go to Section:

Matter –Anything that has mass and occupies space • 1 The basic unit of matter is called the_____. Go to Section:

Matter –Anything that has mass and occupies space • 1 The basic unit of matter is called the atom. Go to Section:

Figure 2 -2 Isotopes of Carbon Section 2 -1 Nonradioactive carbon-12 6 electrons 6 protons 6 neutrons Nonradioactive carbon-13 6 electrons 6 protons 7 neutrons Radioactive carbon-14 6 electrons 6 protons 8 neutrons 2, 3 Atomic _________(electron clouds, nuclei) contain _____ and _____. (protons, electrons, neutrons). (+, -, 0)charge size (0. 0005 amu, 1 amu) where (nucleus, e cloud) • Protons ___ charge size _____ Where? ____ • Neutrons ___ charge size ____ Where? ____ Go to Section: • Electrons ___ charge size ____ Where? ____

Figure 2 -2 Isotopes of Carbon Section 2 -1 Nonradioactive carbon-12 6 electrons 6 protons 6 neutrons Nonradioactive carbon-13 Radioactive carbon-14 6 electrons 6 protons 7 neutrons • 2, 3 Atomic Nuclei contain protons and neutrons. • Protons 1+ charge size 1 amu • Neutrons 0 charge size 1 amu • Electrons 1 - charge size 1/1840 =0. 0005 amu Go to Section: 6 electrons 6 protons 8 neutrons nucleus el cloud

4 Atoms are neutral because they contain the same # of _____ & protons Go to Section:

4 Atoms are neutral because they contain the same # of electrons & protons. Go to Section:

5 Chemical elements are groups of atoms having the same atomic number, that is, atoms having the same number_____. The number of protons in an atom control its identity as an element. These are all atoms of Carbon. All have atomic #_____. Go to Section:

5 Chemical elements are groups of atoms having the same atomic number, that is, atoms having the same number protons. The number of protons in an atom control its identity as an element. These are all atoms of Carbon. All have atomic # 6. Go to Section:

An Element in the Periodic Table Section 2 -1 6 C 12. 011 • 6. Proton # = 6 : shown by the ______ number • • Also, C atoms have 6 electrons: Since atoms are neutral, if you know proton #, you also know ______ #! Go to Section:

An Element in the Periodic Table Section 2 -1 6 C 12. 011 • 6. Proton # = 6 : shown by the atomic number • • Also, C atoms have 6 electrons: Since atoms are neutral, if you know proton #, you also know electron #! Go to Section:

Figure 2 -2 Isotopes of Carbon Section 2 -1 Nonradioactive carbon-12 6 electrons 6 protons 6 neutrons Nonradioactive carbon-13 6 electrons 6 protons 7 neutrons Radioactive carbon-14 6 electrons 6 protons 8 neutrons • 7 Isotopes are forms of the same element that have the same number of protons but a different number of _______ (electrons, neutrons). Go to Section:

Figure 2 -2 Isotopes of Carbon Section 2 -1 Nonradioactive carbon-12 6 electrons 6 protons 6 neutrons Nonradioactive carbon-13 6 electrons 6 protons 7 neutrons Radioactive carbon-14 6 electrons 6 protons 8 neutrons • 7 Isotopes are forms of the same element that have the same number of protons but a different number of neutrons. Go to Section:

Figure 2 -2 Isotopes of Carbon Section 2 -1 Nonradioactive carbon-12 Nonradioactive carbon-13 6 electrons 6 protons 7 neutrons 6 electrons 6 protons 6 neutrons Radioactive carbon-14 6 electrons 6 protons 8 neutrons 8 Isotopes are identified by isotopic notation: Names Carbon-12, carbon-______, carbon-14 OR • 12 C 14 C C • 6 6 Go to Section: 6

Figure 2 -2 Isotopes of Carbon Section 2 -1 Nonradioactive carbon-12 Nonradioactive carbon-13 6 electrons 6 protons 7 neutrons 6 electrons 6 protons 6 neutrons Radioactive carbon-14 6 electrons 6 protons 8 neutrons 8 Isotopes are identified by isotopic notation: Names Carbon-12, carbon-13, carbon-14 OR • 12 C 13 C 14 C • 6 6 Go to Section: 6

9 Isotopes of the same element have the same properties because they have the same atomic number--the same number ______(electrons, neutrons, protons). For C isotopes, this is _____. • 12 • 6 Go to Section: C 13 6 C 14 C 6

9 Isotopes of the same element have the same properties because they have the same atomic number (the same number protons). For C isotopes, this is six protons. • 12 • 6 Go to Section: C 13 6 C 14 C 6

10 Chemical compounds are groups of atoms held together by chemical ____. Chemical compounds are more stable than individual atoms (except for n_______ gas atoms like Ne or Xe) which have stable –filled—valence electron shells. • Chemical compounds allow atoms to obey the “_____ rule”. (2 electrons in the outer electron shell in H and He, but 8 for other elements. ) Go to Section:

10 Chemical compounds are groups of atoms held together by chemical bonds. Chemical compounds are more stable than individual atoms (except for noble gas atoms which have stable ---filled— valence electron shells. • Chemical compounds allow atoms to obey the “octet rule”. (2 electrons in the outer electron shell in H and He, but 8 for other elements. Go to Section:

11 The position of an element in a group/family— column—of the periodic table reveals it # valence or ______ (lowest, highest) energy level electrons. These valence electrons control its chemical reactions. Members of family 16 have ___ valence electrons. Go to Section:

11 The position of an element in a group/family— column—of the periodic table reveals it # valence or highest energy level electrons. These valence electrons control its chemical reactions. Members of family 16 have 4 valence electrons. Go to Section:

12 The periodic table row (period) of an element reveals which of its energy levels is its valence shell. The valence shell for H is the ____ (1 st, 2 nd, 3 rd) energy level, but for Al, it’s the ______, while for C it’s the _____. Go to Section:

12 The periodic table row (period) of an element reveals which of its energy levels is its valence shell. The valence shell for H is the 1 st energy level, but for Al, it’s the 3 rd, while for C it’s the 2 nd. Go to Section:

13 Pure elements are rare because most atoms under chemical reactions to attain a valence energy level octet. Carbon C and other members of family 16 have _____ valence electrons, but to be stable they need ______ more valence electrons. Oxygen O and other members of family 17 have _____ valence electrons, but to be stable, they need _____ more valence electrons. Go to Section:

13 Pure elements are rare because most atoms under chemical reactions to attain a valence energy level octet. Carbon C and other members of family 16 have four valence electrons, but to be stable they need four more valence electrons. Oxygen O and other members of family 17 have seven valence electrons, but to be stable, they need one more valence electron. Go to Section:

14 C_____ f_____ show the numbers of different kinds of atoms bonded together in a single formula unit of a compound • Al 2 O 3 2 Al ions bonded to 3 O ions • Na. Cl ______ Na ion bonded to one Cl ion • Why do we know it’s composed of ions? Because Na is a _______—an electron donor—and Cl is a _____—an electron acceptor –If a metal is present to give it an electron. Go to Section:

14 Chemical formulas show the numbers of different kinds of atoms bonded together in a single formula unit of a compound • Na. Cl one Na ion bonded to one Cl ion • Why do we know it’s composed of ions? Because Na is a metal—an electron donor—and Cl is a nonmetal—an electron acceptor if a metal is present to give it an electron. Go to Section:

15 Atoms in compounds are held together by chemical bonds—either i______ or c_______. Covalent compounds Go to Section:

15 Atoms in compounds are held together by chemical bonds—either ionic or covalent. Go to Section:

Figure 2 -3 Ionic Bonding 16 Ionic bonds: attraction of negative ions to positive ions because a metal donates its _____ to a nonmetal atom, forming stable ions with complete _____ shell octets. Section 2 -1 Sodium ion (Na+) Sodium atom (Na) Chloride ion (Cl-) Chlorine atom (Cl) Transfer of electron Protons +11 Electrons -11 Charge 0 Go to Section: Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1

Figure 2 -3 Ionic Bonding 16 Ionic bonds: attraction of negative ions to positive Section 2 -1 ions because a metal donates its electrons to a nonmetal atom, forming stable ions with complete valence shell octets. Sodium ion (Na+) Sodium atom (Na) Chloride ion (Cl-) Chlorine atom (Cl) Transfer of electron Protons +11 Electrons -11 Charge 0 Go to Section: Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1

17 _____ bonds form when nonmetal atoms share electrons to fill their valence o_______, linking atoms because both nuclei attract the shared electrons. The dots around the nuclei of each atom represent ______. The dots in between two nuceli in the formulas are ________ by the two atoms. The formulas for the c_____ compounds formed below are _____, ______, and ____. Go to Section:

17 Covalent bonds form when nonmetal atoms share electrons to fill their valence octets, linking atoms because both nuclei attract the shared electrons. The dots around the nuclei of each atom represent valence electrons. The dots in between two nuceli in the formulas are shared by the two atoms. The formulas for the covalent compounds formed below are H 2, F 2, CO 2, and CF 4. Go to Section:

Figure 2 -3 Ionic Bonding 18 _____are atoms carrying a charge Section 2 -1 after losing or gaining valence electrons. Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-) Transfer of electron Protons +11 Electrons -11 Charge 0 Go to Section: Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1

Figure 2 -3 Ionic Bonding 18 Ions are atoms carrying a charge after losing or gaining valence electrons. Section 2 -1 Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-) Transfer of electron Protons +11 Electrons -11 Charge 0 Go to Section: Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1

19. True or. False. ______Atom that loses electrons becomes a positive ion. (sodium atoms have 11 protons in the nucleus and 11 neutrons and 11 electrons. Sodium ions have 11 protons, 11 neutrons, and 10 electrons). Go to Section:

19 True or. False. True_Atom that loses electrons becomes a positive ion. (sodium atoms have 11 protons in the nucleus and 11 neutrons and 11 electrons. Sodium ions have 11 protons, 11 neutrons, and 10 electrons). Sodium atom Na Go to Section: Chlorine atom Cl sodium ion Na 1+ chlorine ion Cl 1 -

20. True or. False. _____Nonmetal atoms that gain electrons becomes positive ions. (chlorine atoms have 17 protons in the nucleus and 18 neutrons and 11 electrons. Chlorine ions have 17 protons, 18 neutrons, and 18 electrons). Sodium atom Na Go to Section: Chlorine atom Cl sodium ion Na 1+ chlorine ion Cl 1 -

20. FALSE Nonmetal atoms that gain electrons becomes positive ions. (chlorine atoms have 17 protons in the nucleus and 18 neutrons and 11 electrons. Chlorine ions have 17 protons, 18 neutrons, and 18 electrons). Sodium atom Na Go to Section: Chlorine atom Cl sodium ion Na 1+ chlorine ion Cl 1 -

21. When ionic compounds form, _______ (metals or nonmetals) lose electrons to become _____ (negative or positive) ions because they have ______ (lower or higher) electronegativity than the _____(metals or nonmetals) which take the electrons to become ______(negative or positive) ions. Na Cl Go to Section: Na 1+ Cl 1 -

21. When ionic compounds form, metals lose electrons to become positive ions because they have lower electronegativity than the nonmetals which take the electrons to become negative ions. Metals nonmetals Na Cl Na 1+ Cl 1 - Go to Section:

17 M_____ (Not ionic compounds!) form when atoms are joined with covalent bonds. Covalent bonds form when nonmetals react together. These bonds form between two atoms sharing electrons. Go to Section:

17 Molecules (Not ionic compounds!) form when atoms are joined with covalent bonds. Go to Section:

18 _____ (1, 2, 3, 4, 5, 6, 7 or 8) shared electrons between 2 atoms forms a single covalent bond. ___ (1, 2, 3, 4, 5, 6, 7 or 8) shared electrons is a double covalent bond. _____ (1, 2, 3, 4, 5, 6, 7 or 8) shared electrons is a triple covalent bond Go to Section: http: //academic. brooklyn. cuny. edu/biology/bio 4 f v/page/covalent_bonds. html

18 Two shared electrons between 2 atoms forms a single covalent bond. Four shared electrons is a double covalent bond. Six shared electrons is a triple covalent bond Go to Section: http: //academic. brooklyn. cuny. edu/biology/bio 4 f v/page/covalent_bonds. html

19. In covalent compounds, electrons are shared equally in each covalent bond if the atoms have similar electronegativity. Go to Section:

19 Van Der Waals forces for nonpolar covalent compounds and dipole-dipole interactions for polar covalent compounds hold atoms of nearby molecules together. • Occasionally, valence electrons are nearer one atom than the other in a covalent bond, creating areas partial charge. http: //www. chem. unsw. edu. au/coursenotes/CHEM 1/nonunipass/Haine s. IMF/images/dipole. jpg Go to Section: