CHM Chapter 6

1 mono 2 di 3 tri 4 tetra 5 penta 6 hexa 7 hepta 8 octa 9 nona 10 deca

Prefixes used in naming covalent compounds: 1 2 3 4 5 6 7 8 9 10

a.N-P polar (N)3 - 2.1(P) = 0.9 b. I - I nonpolar (I) 2.5 - 2.5(I) = 0 c. C-O polar (O) 3.5 - 3.0 (C) = 0.5 d. Li-F ionic (F) 4.0 - 1.0 (Li) = 3.1

1) Predict whether each of the following bonds is ionic, polar covalent or nonpolar covalent: a. N-P ___________ b. I-I _____________ c. C-O ____________ d. Li-F _____________

A) gains one electron (Cl is a nonmetal and in7A group, so Cl gains 1 electron)

1)To form an ion, a chlorine (Cl) atom •A) gains one electron •B) gains two electrons. •C) loses seven electrons. •D) loses one electron. •E) loses two electrons.

B) 2+ (Mg is a metal and in 2A group)

2) What is the ionic charge of Magnesium (Mg)? •A) 1+ •B) 2+ •C) 3+ •D) 2- •E) 3-

¨C. 7, 10 (N atom has 7 protons and 7 electrons. N-3 (ion) has 7 protons and gain 3 electrons. So total E = 7 + 3= 10)

A nitrogen atom (atomic number is 7) gains 3 electron and form N-3 ion. Its proton number is ____ and number of electrons is ____ ¨A. 7, 7 ¨B. 8, 7. ¨C. 7, 10 ¨ D. 7, 5

A. Na+ and O2− 2) Na2O Check: 2Na+ + O2− = 2(1+) + 1(2−) = 0 B. Al3+ and Cl− 1) AlCl3 Check: Al3+ + 3Cl− = (3+) + 3(1−) = 0 C. Mg2+ and N3− 3) Mg3N2 Check: 3Mg2+ + 2N3− = 2(3+) + 2(3−) = 0

Select the correct formula for each of the following ionic compounds. A. Na+ and O2− 1) NaO 2) Na2O 3) NaO2 B. Al3+ and Cl− 1) AlCl3 2) AlCl 3) Al3Cl C. Mg2+ and N3− 1) MgN 2) Mg2N3 3) Mg3N2

A. aluminum nitrate 3) Al(NO3)3 B. copper(II) nitrate 2) Cu(NO3)2 C. iron(III) hydroxide 3) Fe(OH)3 D. tin(IV) hydroxide 1) Sn(OH)4

Select the correct formula for each. A. aluminum nitrate B. copper(II) nitrate C. iron(III) hydroxide D. tin(IV) hydroxide

A. 3) silicon tetrachloride B. 3) diphosphorus pentoxide C. 1) dichlorine heptoxide

Select the correct name for each compound. A. SiCl4 1) silicon chloride 2) tetrasilicon chloride 3) silicon tetrachloride B. P2O5 1) phosphorus oxide 2) phosphorus pentoxide 3) diphosphorus pentoxide C. Cl2O7 1) dichlorine heptoxide 2) dichlorine oxide 3) chlorine heptoxide

Step 1. find metal with charge and nonmetal with charge from the periodic table Step 2. total positive charge (find charges in the periodic table) = total negative charge (find charges from the periodic table) therefore total positive charge + total negative charge = 0 Step 3. Subscripts in ionic compound represent the number of positive and negative ions that give an overall charge of zero.

Steps for writing an ionic compound formula:

b. polar covalent (N) 3 - 3.5 (Cl) = 0.5

The bond between sodium chloride is a. ionic b. polar covalent. c. not formed. d. Nonpolar covalent.

•the lowercase Greek letter delta with a positive (less electronegativity) or negative (more electronegativity) charge •an arrow that points from the positive to the negative end of the dipole

The positive and negative ends of the dipole are located by using

metal; nonmetal

The symbol of the ____ is written first, followed by the symbol of the ____.

Cu2+ copper(II) Pb2+ lead(II) Cu+ copper(I) Pb4+ lead(IV) Fe2+ iron(II) Cr3+ chromium(III) Fe3+ iron(III) Cr6+ chromium(VI)

Transition metals except for Zn2+, Cd2+, and Ag+ form two or more positive ions (cations). We use a Roman numeral to identify ionic charge. Cu2+ Pb2+ Cu+ Pb4+ Fe2+ Cr3+ Fe3+ Cr6+

A. K-N 2.2 ionic (I) B. N-O 0.5 polar covalent (P) C. Cl-Cl 0.0 nonpolar covalent (NP) D. H-Cl 0.9 polar covalent (P)

Use the electronegativity difference to identify the type of bond [nonpolar covalent (NP), polar covalent (P), or ionic (I)] between the following: A. K-N B. N-O C. Cl-Cl D. H-Cl

Step 1. find charge of Cu by reverse subscribe CuCl2 Cu +2 charge, Cl -1 charge Step 2. charge of Cu is represent by roman numeral copper (II) Step 3. Name the anion by using the first syllable of its element name followed by ide. chloride Step 4. Write the name of copper first and the name of the chloride second. copper(II)chloride

What is name of CuCl2 ?

-the first nonmetal in the formula is named by its element name -the second nonmetal is named by using the first syllable of its name followed by ide -if a subscript is used in the formula a prefix is used in front of its name -when vowels o and o or a and o appear together, the first vowel is omitted

When naming covalent compounds:

D) lose 3 ( Aluminum is a metal and it is in 3A group in the periodic table)

How many electrons will aluminum gain or lose when it forms an ion? •A) lose 1 •B) gain 5 •C) lose 2 •D) lose 3 •E) gain 1

A. SO3 covalent - sulfur trioxide B. BaCl2 ionic - barium chloride C. (NH4)3PO3 ionic - ammonium phosphite D. Cu2CO3 ionic - copper(I) carbonate E. N2O4 covalent - dinitrogen tetroxide

Identify each compound as ionic or covalent, and give its correct name. A. SO3 B. BaCl2 C. (NH4)3PO3 D. Cu2CO3 E. N2O4

sodium

___ atoms in Group 1A (1) are neutral, with 11 electrons and 11 protons. They •lose one electron to have the same number of valence electrons as neon and a filled energy level •will form an ion with 10 electrons and 11 protons, and an ionic charge of 1+, Na+

ionic

___ if the first element in the formula or the name is a metal or the polyatomic ion NH4+

Covalent

___ if the first element in the formula or the name is a nonmetal

subcripts

___ in ionic compound represent the number of positive and negative ions that give an overall charge of zero. total positive charge + total negative charge = 0 therefore, total positive charge = total negative charge

chemical bond

___ is an attraction between atoms that allows the formation of chemical substances that contain two or more atoms.

polar covalent bond

___ occurs between nonmetal atoms. It is an unequal sharing of electrons and has a moderate electronegativity difference (0.4-1.7).

nonpolar covalent bond

___ occurs between nonmetals. It is an equal or almost equal sharing of electrons and has a very small electronegativity difference (less or equal to 0.4)

magnesium

____ atoms in Group 2A (2) are neutral. They have12 electrons and 12 protons, and they •will lose two electrons to have the same number of valence electrons as neon and a filled energy level •form an ion with 10 electrons and 12 protons, and an ionic charge of 2+, Mg2+

polar covalent bond; dipole

____ becomes more polar as the difference in electronegativity increases. The separation of charges in a polar bond is called a ____

chemical

____ bonds are formed when atoms lose, gain, or share valence electrons to acquire an octet of eight valence electrons (octet rule).

hydrogen

____ bonds are the strongest force between molecules and play a major role in the shape of DNA.

covalent

____ bonds occur when nonmetal atoms share electrons to attain a noble gas arrangement.

ionic

____ bonds occur when the atoms of one element lose valence electrons and the atoms of another element gain valence electrons.

metals

____ form positive ions •by a loss of their valence electrons •with the electron configuration of the nearest noble gas •that have fewer electrons than protons

ionic bonds

____ occurs between metal and nonmetal ions. It is a result of electron transfer and has a large electronegativity difference (1.8 or more)

covalent compounds

_____ form •when atoms share electrons to complete octets •between nonmetal atoms from Groups 4A, 5A, 6A, and 7A

nonmetals

____form negative ions: •by a gain of valence electrons •with the electron configuration of the nearest noble gas •with fewer protons than electrons Group 5A nonmetals ion 3− Group 6A nonmetals ion 2− Group 7A nonmetals ion 1−

Number Number Bonds Lone Pairs Geometry A. PBr3 3 1 trigonal pyrimidal The dipoles do not cancel; the molecule is polar. B. HBr 1 0 linear The bond has a dipole; the molecule is polar. C. CF4 4 0 tetrahedral The bonds have dipoles; the dipoles cancel and the molecule is nonpolar.

Identify each of the following molecules as polar or nonpolar. Explain. A. PBr3 B. HBr C. CF4

A. NCl3 (polar) dipole-dipole forces B. H2O (polar) (H with O) hydrogen bonds C. Br-Br (nonpolar) dispersion forces D. KCl (ionic) ionic bonds E. NH3 (polar) (H with N) hydrogen bonds

Identify the main type of attractive forces that are present in liquids of the following compounds: ionic bonds, dipole-dipole, hydrogen bonds, or dispersion forces. A. NCl3 B. H2O C. Br-Br D. KCl E. NH3

central atom with three electron groups

In a molecule of BF3 •there are only three electron groups around the central atom, B, which is an exception to octet rule •repulsion is minimized by placing the three groups as far apart as possible at bond angles of 120° •the shape with three electron groups around the central atom is trigonal planar In a molecule of SO2 •there are three electron groups around the central atom S: a single-bonded O atom, a double-bonded O atom, and a lone pair of electrons •repulsion is minimized by placing the three groups as far apart as possible •since one group is a lone pair, the shape is determined by the two O atoms bonded to S, giving the molecule its bent shape

Central atom with two electron groups

In a molecule of BeCl2 •there are only two electron groups around the central atom, Be, which is an exception to octet rule •repulsion is minimized by placing the two groups on opposite sides of the Be atom, giving this a linear arrangement with bond angles of 180° •the shape with two electron groups around the central atom is linear

Step 1 Identify the cation and anion. The cation, K+, is from Group 1A, and the anion, O2−, is from Group 6A. Step 2 Name the cation by its element name. The cation, K+, is potassium. Step 3 Name the anion by using the first syllable of its element name followed by ide. The anion, O2−, is oxide. Step 4 Write the name of the cation first and the name of the anion second. K2O is named potassium oxide.

Name the ionic compound K2O:

a. N-P polar (N)3 - 2.1(P) = 0.9 N ∞ - P∞+ b. F - Cl polar (F) 4 - 3(Cl) = 1.0 F ∞ - Cl∞+ c. C-O polar (O) 3.5 - 3.0 (C) = 0.5 O ∞ - C ∞+ d. Na-F ionic (F) 4.0 - 0.9 (Na) = 3.1

a. Predict whether each of the following bonds is ionic, polar covalent or nonpolar covalent: b. If it is polar covalent, indicate which one has delta positive, which has detal negative a. N-P ___________ b. F - Cl________ c. C-O ____________ d. Na-F _____________

•D) 2- (S is a nonmetal and is in 6A group. S gains 2 electrons to reach 8 electrons in outmost shell)

•2) What is the ionic charge of sulfide (S) ion? • •A) 1+ •B) 2+ •C) 3+ •D) 2- •E) 3-

polyatomic ions

•are a group of atoms with an overall charge •often consist of a nonmetal such as phosphorus, sulfur, carbon, or nitrogen and oxygen •usually have a 1−, 2−, or 3− charge

polar molecules

•because one end of the molecule is more negatively charged than the other •when polar bonds in the molecule do not cancel each other •because the electrons are shared unequally in the polar covalent bond •with three or more atoms, the shape of the molecule determines whether the dipoles cancel or not •there are often lone pairs around the central atom •such as H2O, the dipoles do not cancel, making the molecule positive at one end and negative at the other end •such as H2O, there is a dipole on the central atom

ionic compounds

•consist of positive and negative ions •have attractions called ionic bonds between positively and negatively charged ions •have high melting points •are solid at room temperature

ionic formula (M+ + -NM)

•consists of positively and negatively charged ions • is neutral • has charge balance total positive charge = total negative charge

nitrogen molecule, N2

•each N atom shares three electrons to gain an octet •the multiple bond formed is called a triple bond •the name is the same as the element

hydrogen molecule H2

•forms as the atoms move closer and the nucleus of one atom attracts the electron of the other •is stable with 2 electrons (helium) has a shared pair of electrons

Nonmetals—Group 5A (15), Group 6A (16), and Group 7A (17)—

•have high ionization energies •readily gain one or more valence electrons to form ions with a negative charge in ionic compounds •gain electrons until they have the same number of valence electrons as the nearest noble gas, usually eight valence electrons

Metals---- group 1A (1), group 2A (2), and group 3A (13)

•have low ionization energies •readily lose one or more of their valence electrons to form ions with a positive charge •lose electrons until they have the same number of valence electrons as the nearest noble gas, usually eight valence electrons

ionic bond

•occurs between metal and nonmetal ions •is a result of electron transfer (mental loses e-, nonmetal gains e-) •has a large electronegativity difference (1.8 or more)

polar covalent bonds

•occurs between nonmetal atoms •is an unequal sharing of electrons •has a moderate electronegativity difference

nonpolar covalent bonds

•occurs between nonmetals •is an equal or almost equal sharing of electrons •has a very small electronegativity difference

triple bond

•occurs when atoms share three pairs of electrons •forms when there are not enough electrons to complete octets

double bond

•occurs when atoms share two pairs of electrons forms when there are not enough electrons to complete octets

Electronegativity value

•of an element indicates the attraction of an atom for the shared electrons in a bond •increases from left to right going across a period on the periodic table •is high for the nonmetals, with fluorine as the highest •is low for the metals

melting points

•of compounds are related to the strength of attractive forces between molecules or compounds •are lower due to weak forces such as dispersion forces •are higher due to stronger attractive forces such as hydrogen bonding •are highest in ionic compounds due to the strong attractive forces between ions in the compound

nonpolar molecules

•such as H2, Cl2, and O2 are nonpolar because they contain nonpolar bonds •with polar bonds such as CO2 can be nonpolar if the polar bonds cancel each other in a symmetrical arrangement •dipoles cancel out, which makes the molecule nonpolar

dispersion forces

•weak attractions between nonpolar molecules •caused by temporary dipoles that develop when molecules bump into each other •weak, but make it possible for nonpolar molecules to form liquids and solids

the octet rule

states that elements gain or lose electrons and become ions to attain noble gas arrangement.

Group 1A 1+ Group 2A 2+ Positive Charges Group 3A 3+ Group 5A 3− Group 6A 2− Negative Charges Group 7A 1−

Group 1A Group 2A Group 3A Group 5A Group 6A Group 7A

Group 1A metals ion 1+ Group 2A metals ion 2+ Group 3A metals ion 3+

Group 1A metals ion __ Group 2A metals ion __ Group 3A metals ion ___

A. Identify each as a metal or a nonmetal. metal = calcium nonmetal = chlorine B. State the number of valence electrons for each. Calcium has two valence electrons. Chlorine has seven valence electrons. C. State the number of electrons that must be lost or gained for each to acquire an octet. Calcium will lose 2 electrons to acquire an octet. Chlorine will gain 1 electron to reach 8 electrons in outmost shell (octet rule) . D. Write the symbol, including its ionic charge, and name of each resulting ion. Ca2+ calcium Cl− chloride

Consider the elements calcium and chlorine. A. Identify each as a metal or a nonmetal. B. State the number of valence electrons for each. C. State the number of electrons that must be lost or gained for each to acquire an octet. D. Write the symbol, including its ionic charge, and name of each resulting ion.

¨Step 1. Have to be a nonmetal (can be found in the periodic table) ¨Step 2. Have to gain electron to reach eight (8) in their outmost shell. If a nonmetal has 5 valence electrons, it needs to gain 3 electrons to reach 8 electrons in its outmost shell.

Determining a negative (-) ions involves two steps:

•Step 1. Have to be a metal (can be found in the periodic table) •Step 2. Have to lose their valence electrons (valence electrons = A group numbers in the periodic table). If a metal has 1 valence electron, it loses 1 electron to form a + 1 charge ion.

Determining the positive (+) ions involves two steps:

central atom with four electron groups

In a molecule of CH4 •there are four electron groups attached to H atoms around the central atom, C •repulsion is minimized by placing the four groups at corners of a tetrahedron with bond angles of 109° •the shape with four bonds on the central atom is called tetrahedral In a molecule of NH3 •there are three electron groups attached to H atoms and a lone pair around the central atom, N •repulsion is minimized by placing the four groups at corners of a tetrahedron with bond angles of 109° •the shape with three bonds on the central atom is called trigonal pyrimidal In a molecule of H2O •there are two electron groups attached to H atoms and two lone pairs around the central atom, O •repulsion is minimized by placing the four groups at corners of a tetrahedron with bond angles of 109° •the shape with two bonds on the central atom is called bent ¨

less than the number of electrons, so net charge is (-).

In a negative ion, the number of protons is

great than number of electrons, so net charge is (+).

In a positive ion, the number of protons is

number of electrons, so net charge is 0

In an atom, the number of protons =

number of electrons .

In an ion, the number of protons ≠

dipole-dipole attractions

In covalent compounds, polar molecules exert attractive forces called

A. magnesium sulfite B. magnesium sulfate C. calcium chlorate

Name each of the following compounds containing polyatomic ions. A. MgSO3 B. MgSO4 C.Ca(ClO3)2

A. Iron (III) sulfate B. Barium Phosphite C. lead (II) carbonate

Name each of the following compounds: A. Fe2(SO4)3 B. Ba3(PO3)2 C. PbCO3

Step 1 Name the first nonmetal by its element name. The first nonmetal (N) is nitrogen. Step 2 Name the second element by using the first syllable of its name followed by ide. The second nonmetal (Cl) is chloride. Add prefixes to indicate number of atoms. Because there is one nitrogen atom, no prefix is needed. The subscript three for the Cl atoms is shown as the prefix tri. NCl3, nitrogen trichloride

Name the covalent compound NCl3.

Step 1 Determine the charge of the cation. A. Fe2O3 Fe has +3 charge, O has -2 charge B. SnCl2 Sn has +2 charge, Cl has -1 charge Step 2 Name the cation by its element name and use a Roman numeral in parenthesis for the charge. A. Fe2O3 The charge on Fe is represented by a Roman numeral: iron(III) B. SnCl2 The charge on Sn is represented by a Roman numeral: tin(II) Step 3 Name the anion by using the first syllable of its element name followed by ide. A. Fe2O3 Oxygen becomes oxide. B.SnCl2Chlorine becomes chloride. Step 4 Write the name of the cation first and the name of the anion second. A. Fe2O3 is iron(III) oxide. B. SnCl2 is tin(II) chloride.

Name the following ionic compounds containing metals that form two kinds of positive ions: A. Fe2O3 B. SnCl2

A. calcium nitrate B. iron (III) phosphate

Name the following ionic compounds: A. Ca(NO3)2 B. FePO4

Step 1 Determine the charge of the cation. Because there are two Cl− anions, the charge on the Fe ion must be 2+. Step 2 Name the cation by its element name and use a Roman numeral in parenthesis for the charge. The charge on Fe is represented by a Roman numeral, iron(II). Step 3 Name the anion by using the first syllable of its element name followed by ide. Chlorine becomes chloride. Step 4 Write the name of the cation first and the name of the anion second. The ionic compound is named iron(II) chloride.

Name the ionic compound FeCl2.

Write chemical formulas for the following compounds. Step 1 Identify the cation and anion. A. Nickel(II) sulfide The Roman numeral (II) indicates that the charge on the nickel ion is 2+, Ni2+. B. Zinc chloride Zinc is one of the transition metals with a fixed charge of 2+, Zn2+. C. Iron(III) oxide The Roman numeral (III) indicates that the charge on the iron ion is 3+, Fe3+. Step 2 Balance the charges. A. Nickel(II) sulfide Ni2+ S2− 1(2+) + 1(2−) = 0 B. Zinc chloride Zn2+ Cl− Cl− 1(2+) + 2(1−) = 0 Balance the charges. C. Iron(III) oxide Fe3+ O2− 2(3+) + 3(2−) = 0 Step 3 Write formula, cation first using subscripts from the charge balance. A. Nickel(II) sulfide NiS B. Zinc chloride ZnCl2 C. Iron(III) oxide Fe2O3

Write chemical formulas for the following compounds: A. Nickel(II) sulfide B. Zinc chloride C. Iron(III) oxide

Step 1. Na is metal with +1, S is nonmetal with -2, Na +1 S -2 Step 2. charge balance is used to write the formula for sodium nitride, a compound containing Na+ and S2−. Na+ 2 Na+ + S2− = Na2S 2(+1) + 1(2−) = 0 Formula Na2S

Write formula of a compound with Na and S

Step 1 Write the symbols in order of the elements in the name. A. phosphorus pentachloride The first nonmetal is phosphorus, (P) and the second nonmetal is chlorine, (Cl). P Cl B. dinitrogen trioxide The first nonmetal is nitrogen, (N) and the second nonmetal is oxygen, (O). N O C. sulfur hexafluoride The first nonmetal is sulfur, (S) and the second nonmetal is fluorine, (F). S F Step 2 Write any prefixes as subscripts. A. phosphorus pentachloride: No prefix for phosphorus indicates there is 1 phosphorus atom. The prefix penta in pentachloride indicates there are 5 chlorine atoms, and is shown as a subscript after Cl. PCl5 B. dinitrogen trioxide: The prefix di in dinitrogen indicates there are 2 nitrogen atoms and is shown as a subscript after N. The prefix tri in trioxide indicates there are 3 oxygen atoms and is shown as a subscript after O. N2O3 C. sulfur hexafluoride: No prefix for sulfur indicates there is 1 sulfur atom. The prefix hexa in hexafluoride indicates there are 6 fluorine atoms and is shown as a subscript after F. SF6

Write the correct formula for each of the following: A. phosphorus pentachloride B. dinitrogen trioxide C. sulfur hexafluoride

The element with 16 protons is sulfur, with the symbol S. An ion of sulfur with 18 electrons gives sulfur a charge of 2−. The sulfide ion is S2−.

Write the formula and symbol of an ion with 16 protons and 18 electrons.

Step 1 Write the symbols in order of the elements in the name. The first nonmetal is boron (B) and the second nonmetal is oxygen (O). B O Step 2 Write any prefixes as subscripts. The prefix di in diboron indicates there are two boron atoms and is shown as a subscript after B. The prefix tri in trioxide indicates there are three oxygen atoms and is shown as a subscript after O. B2O3

Write the formula for the covalent compound diboron trioxide.

Br− S2− N3− NaBr Na2S Na3N Na+. sodium sodium sodium bromide sulfide nitride AlBr3 Al2S3 AlN Al3+ aluminum aluminum aluminum bromide sulfide nitride

Write the formulas and names for compounds of the following ions: Br− S2− N3− Na+ Al3+

Ba2+ Cl− Balance the charges: Ba2+ + 2 Cl− Cl− = BaCl2 2+ + 2(1−) = 0 Write the ionic formula using a subscript 2 for two chloride ions.

Write the ionic formula of the compound formed with Ba2+ and Cl− ions.

Step 1 Name the first nonmetal by its element name. A. CO The first nonmetal (C) is carbon. B. NO2 The first nonmetal (N) is nitrogen. C. PF3 The first nonmetal (P) is phosphorus. D. CCl4 The first nonmetal (C) is carbon. Step 2 Name the second element by using the first syllable of its name followed by ide. A. CO The second nonmetal (O) is oxide. B. NO2 The second nonmetal (O) is oxide. C. PF3 The second nonmetal (F) is fluoride. D. CCl4 The second nonmetal (Cl) is chloride. Step 3 Add prefixes to indicate number of atoms. A. CO Because there is one carbon atom, no prefix is needed. The subscript 1 for the O atom is shown using the prefix mono. CO is carbon monoxide. B.NO2Because there is one nitrogen atom, no prefix isneeded.The subscript 2 for the O atoms isshown using the prefix di.NO2 is nitrogen dioxide. C. PF3 Because there is one phosphorus atom, no prefix is needed. The subscript 3 for F atoms is shown using the prefix tri. PF3 is phosphorus trifluoride. D. CCl4 Because there is one carbon atom, no prefix is needed. The subscript 4 for the Cl atoms is shown using the prefix tetra. CCl4 is carbon tetrachloride.

Write the name of each covalent compound. A. CO B. NO2 C. PF3 D. CCl4

Step 1 Identify the cation and anion. A. CaO: The cation, Ca2+, is from Group 2A, and the anion, O2−, is from Group 6A. B. Al2O3: The cation, Al3+, is from Group 3A, and the anion, O2−, is from Group 6A. C. MgCl2: The cation, Mg2+, is from Group 2A, and the anion, Cl−, is from Group 7A. Step 2 Name the cation by its element name. A. CaO The cation, Ca2+, is calcium. B. Al2O3 The cation, Al3+, is aluminum. C. MgCl2 The cation, Mg2+, is magnesium. Step 3 Name the anion by using the first syllable of its element name followed by ide. A. CaO The anion, O2−, is oxide. B. Al2O3 The anion, O2−, is oxide. C. MgCl2 The anion, Cl−, is chloride. Step 4 Write the name of the cation first and the name of the anion second. A. The name of CaO is calcium oxide. B. The name of Al2O3 is aluminum oxide. C. The name of MgCl2 is magnesium chloride.

Write the names of the following compounds. A. CaO ___________ B. Al2O3 ___________ C. MgCl2 ___________

1) CaO calcium oxide 2) KBr potassium bromide 3) Al2O3 aluminum oxide 4) MgCl2 magnesium chloride

Write the names of the following compounds: 1) CaO ___________ 2) KBr ___________ 3) Al2O3 ___________ 4) MgCl2 ___________

ionic bonds

are formed by the strong attractive forces between positive and negative ions.

chlroine

atoms in Group 7A (17) are neutral. They have 17 electrons and 17 protons, and they •will gain one electron to have the same number of valence electrons as argon and a filled energy level •form an ion with 18 electrons and 17 protons, and an ionic charge of 1−, Cl−

ionic bonds, polar covalent bonds, and nonpolar covalent bonds

chemical bonds include ____

atom

form positively charged ions when they lose electrons and negatively charged ions when they gain electrons.

hydrogen bonds

in covalent compounds, polar molecules form strong dipole attractions called _____ between hydrogen atoms bonded to very electronegative atoms of F, O, or N

octet

is eight valence electrons is associated with the stability of the noble gases (except He)