CHM 130 Chapter 12
Trigonal Planar Molecules Ex. CH₂O Has 14 v.e. or 7 pairs Double Bonds Or 4/0 120°
The central atom is surrounded by single and double bonds Notice that the lone pairs on O do not matter because it is not the central atom. Geometry: Trigonal Planar Molecular shape: Trigonal Planar
Trigonal Pyramidal Molecules Ex. NH₃ Has 8 v.e. or 4 pairs 3 bonding pairs and 1 red lone pair Or 3/1 107.3°
The central atom is surrounded by three bonding pairs and one non bonding pair (lone pair). Geometry: Tetrahedral Molecular shape: Trigonal Pyramidal
What is the chemical formula for barium phosphate?
a) BaPO₃ b) BaPO₄ c) *Ba₃(PO₄)₂* d) Ba₂(PO₄)₃
What is the chemical formula for cobalt (II) bromide?
a) Co₂Br b) *CoBr₂* c) Co₃Br₂ d) Co₂Br₃
Which of the following metals reacts with aqueous AgNO₃? Partial Activity Series: Fe > Co > (H) > Cu > Ag
a) Fe b) Co c) Cu d) *all of the above*
Fe₃(PO₄)²
iron (II) phosphate
What is the term for a bond in which a pair of electrons is shared equally?
nonpolar covalent bond
What is the term for the statement that an atom tends to bond in such a way so as to acquire eight valence electrons?
octet rule
What is the term for a bond in which a pair of electrons is not shared equally?
polar covalent bond
K₃N
potassium nitride
aqueous solution
produced when a compound dissolved in water
What is the electron pair geometry for a hydrogen sulfide molecule H₂S?
tetrahedral
S₃O₆
trisulfur hexoxide
Hydrogen Bonds
•Bonds between highly electronegative atoms and other highly electronegative atoms. •Bonds between Hydrogen and: o Nitrogen o Oxygen o Fluorine o Carbon •It is a polar covalent bond. o O is ẟ- o H is ẟ+ •Attraction between negative pull and positive push •Between 2 non-metals so it is covalent •Not intramolecular because it is between two molecules so it is intermolecular
Ammonium phosphate
(NH₄)₃PO₄
According to the general trends in the periodic table which of the following is the most electronegative element?
(a) C (b) N (c) P (d) *O*
Predict which of the following is connected by an ionic bond.
(a) CaO (b) FeO (c) SnO (d) *all of the above*
What is the chemical formula for the copper(I) ion?
(a) Co⁺ (b) Co²⁺ (c) *Cu⁺* (d) Cu²⁺
What is the Stock system name for Mn₃N₂?
(a) manganese nitride (b) manganous nitride (c) *manganese(II) nitride* (d) manganese(III) nitride
What is the systematic name for N ?
(a) nitrogen ion (b) *nitride ion* (c) nitrite ion (d) nitrate ion
Which of the following cations is isoelectronic with argon?
(a) potassium ion (b) calcium ion (c) scandium ion (d) *all of the above*
Draw the structural formula for nitrogen N₂, and state the type of bond in a nitrogen molecule.
1 triple bond
Metal + Nonmetal Reactions
A metal and a nonmetal react in a combination reaction to give an ionic compound. metal + nonmetal → ionic compound Sodium reacts with chlorine gas to produce sodium chloride. 2 Na(s) + Cl2(g) → 2 NaCl(s) When a main group metal reacts with a nonmetal, the formula of the ionic compound is predictable. If the compound contains a transition metal, the formula is not predictable.
Br⁻
A monoatomic anion. Bromide ion. Group V
Neutralization Reactions
A neutralization reaction is the reaction of an acid and a base. HX + BOH → BX + HOH A neutralization reaction produces a salt and water. H2SO4(aq) + 2 KOH(aq) → K2SO4(aq) + 2 H2O(l)
Single-Replacement Reactions
A single-replacement reaction is a reaction in which a more active metal displaces another less active metal in a compound. If a metal precedes another in the activity series, it will undergo a single-replacement reaction. Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s)
Metal and Nonmetal ↓ ↓ Lose e- Gain e+ ↓ ↓ Cations Anions
Al → 1s²2s²2p⁶3s²3p¹ Will lose 3 electrons. Cl → 1s²2s²2p⁶3s²3p⁵ Has 7 electrons - needs 3. Chemical formula: AlCl₃ Once it is a compound it is neutral No charges are in the formula
What is the coefficient of AgCl after balancing the following equation? AlCl₃(aq) + AgNO₃(aq) → Al(NO₃)₃(aq) + AgCl(s)
AlCl₃(aq) + AgNO₃(aq) → Al(NO₃)₃(aq) + AgCl(s) (a) 1 (b) 2 (c) *3* (d) 6
Ternary Oxyacid
An acqueous solution containing three elements HO and some other: ex. HNO₃ (aq) HClO (aq) hypochlorous acid HClO₂ (aq) chlorous acid HClO₃ (aq) chloric acid HClO₄ (aq) perchloric acid
Balance the following chemical equations. 3. Au2S3 + H2 Au + H2S
Au2S3 + H2 Au + H2S
Electron dot formula for BO₃³⁻? aka Trioxoborate ion
BO₃³⁻ B has 3 valence electrons (needs 5)= 3 e O has 6 ve x 3 atoms = 18e
Why metals lose electrons?
Be 1s²2S² rather lose 2 than gain 6 Al 1s²2s²2p⁶3s²3p¹ rather lose 3 than gain 5 This is why metals like to lose. It is easier to lose than gain.
Aqueous Acid
Binary Acid Ternary Oxyacid
Ionic inorganic compounds
Binary Ionic Compound Ternary Ionic Compound
Molecular Inorganic Compound
Binary Molecular Compound
Ionic Bonds
Bonds that are formed by attraction between positively charged anions and negatively charged anions. This electrostatic attraction is similar to opposite poles on two magnets. Always have attraction whether its + or - ₁₁Na→ 1s²2s²2p⁶3s¹ (1 electron in outer shell) ₁₇Cl→ 1s¹2s²2p⁶3s²3p⁵ (7 electrons in outer shell) ₁₁Na+ Protons = 11 electrons minus 1 Electrons = 10 ₁₇Cl- Protons = 17 electrons plus 1 Electrons = 18 Neutral + Charged ion - called CATION - Charged Ion - called ANION
Electron dot formula for CS₂? aka carbon disulfide
C S₂ ↓ ↓ 4 + (2)6 =16 electrons (8 pairs) Carbon needs 4
What is the coefficient of hydrogen gas after balancing the following equation? Ca(s) + H₂O(l) → Ca(OH)₂(aq) + H₂(g)
Ca(s) + H₂O(l) → Ca(OH)₂(aq) + H₂(g) (a) *1* (b) 2 (c) 3 (d) 4
Calcium oxide
CaO
What is the coefficient of hydrogen gas after balancing the following equation? Co(s) + HCl(aq) → CoCl₃(aq) + H₂(g)
Co(s) + HCl(aq) → CoCl₃(aq) + H₂(g) (a) 1 (b) 2 (c) *3* (d) 4
Polyatomic anions
Contain one or more elements combined with oxygen - these are called oxyanions. ∙ Most end in -ate ∙ SO₄²⁻ sulfate ion ∙ NO₃⁻ nitrate ion Some are oxyanions that end in -ite ∙ SO₃²⁻ sulfite ion ∙ NO₂⁻ nitrite ion
What is the coefficient of NaCl after balancing the following equation? CrCl₃(aq) + Na₂CO₃(aq) → Cr₂(CO₃)₃(s) + NaCl(aq)
CrCl₃(aq) + Na₂CO₃(aq) → Cr₂(CO₃)₃(s) + NaCl(aq) (a) 1 (b) 2 (c) 3 (d) *6*
Chromium (III) phosphide
CrP
What is the coefficient of carbon dioxide after balancing the following equation? Cr₂(CO₃)₃(s)→ Cr₂O₃(s) + CO₂(g)
Cr₂(CO₃)₃(s)→ Cr₂O₃(s) + CO₂(g) (a) 1 (b) 2 (c) *3* (d) 4
Copper (II) nitrate
Cu(NO₃)₂
Electronegativity
Each element has an innate ability to attract valence electrons • Electronegativity is the ability of an atom to attract electrons in a chemical bond. • Linus Pauling devised a method in a shared covalent bond a method for measuring the electronegativity of each of the elements. • Fluorine is the most electronegative element
SHAPES OF MOLECULES-Valence Shell Electron Pair Repulsion Theory (VSPER) theory
Electron pairs surrounding an atom repel each other The electron pair geometry indicates the arrangement of bonding and nonbonding electron pairs around the central atom. The molecular shape indicates the arrangement of atoms around the central atom as a result of electron repulsion.
Bond Energy
Energy is released when two atoms form a covalent bond. CH(g) + Cl(g) HCl(g) + heat Conversely, energy is needed to break a covalent bond. The energy required to break a covalent bond is referred to as the bond energy. The amount of energy required to break a covalent bond is the same as the amount of energy released when the bond is formed. HCl(g) + heat H(g) + Cl(g) Heat is formed when the two atoms are combined to fill the shell and energy is released. If you want to break it you need to put in heat. Bond energy is the minimum energy to break a covalent bond.
What is the coefficient of nickel metal after balancing the following equation? Fe(s) + Ni(NO₃)₂(aq) → Fe(NO₃)₃(aq) + Ni(s)
Fe(s) + Ni(NO3)2(aq) → Fe(NO3)3(aq) + Ni(s) a) 1 b) 2 c) *3* d) 4
Iron (II) sulfide
FeS
Chemical Bond
Force of attraction between elements A→←B A − B
Cations
Formed when an atom loses valence electrons to become positively charged.
Covalent Bonds
Formed when two nonmetal atoms share electrons, and the shared electrons in the covalent bond belong to both atoms.
Monoatomic ion charges by Group
Group IA +1 Group IIA +2 Group IIIA + 3 Group IVA +4or-4 Group VA -3 Group VIA -2 Group VIIA -1
Electron dot formula for HOCI? aka Hypochlorous acid
H O Cl ↓ ↓ ↓ 1+ 6 + 7 = 14 elections (7 pairs)
Ex of Polar Covalent Bond A ẟ+ - B ẟ-
H-F F has 7 electrons and H has 1 electron. Therefore 90% of the electrons are closer to the fluorine nucleus. This is considered a polar covalent bond. H+-F- Sharing even though not equally.
5. H3PO4 Hg3(PO4)2 + H2O
H3PO4 Hg3(PO4)2 + H2O
8. HClO4 + P4O10 H3PO4 + Cl2O7
HClO4 + P4O10 H3PO4 + Cl2O7
Tetrahedral Molecules Ex. CH₄ Has 8 v.e. or 4 pairs 4 bonding pairs or 4/0 109.5°
Has four pairs around the central carbon atom The four bonding pairs (and therefore atoms are repelled to the four corners of a tetrahedron. (4) face figure Geometry: Tetrahedral Molecular shape: Tetrahedral
What seven molecules occur naturally as diatomic?
Hydrogen (H2) Nitrogen (N2) Oxygen (O2) Halogen F2 Halogen Cl2 Halogen Br2 Halogen I2
What is the coefficient of oxygen gas after balancing the following equation? H₂O₂(l) → H₂O(l) + O₂(g)
H₂O₂(l) → H₂O(l) + O₂(g) a) *1* b) 2 c) 3 d) 4
Hydrosulfuric acid
H₂S
Phosphorous acid
H₃PO₃
How do you know it is a covalent bond?
H→1s¹ (Doesn't want to lose the only electron it has) Cl→ 1s²2s²2p⁶3s²3p⁵ (7 electrons so it can't gain and it needs to share) They will not transfer so it will need to share - not ionic or it could transfer.
Nonpolar covalent bonds
If the atoms are less than 0.5 they are not polarized and therefore they have the same or similar electronegativities
MEMORIZE THIS CHART
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Decomposition Reactions
In a decomposition reaction, a single compound is broken down into simpler substances. Heat or light is usually required to start a decomposition reaction. Ionic compounds containing oxygen often decompose into a metal and oxygen gas. For example, heating solid mercury(II) oxide produces mercury metal and oxygen gas. 2 HgO(s) → 2 Hg(l) + O2(g)
Double-Replacement Reactions
In a double-replacement reaction, two ionic compounds in aqueous solution switch anions and produce two new compounds. AX + BZ → AZ + BX If either AZ or BX is an insoluble compound, a precipitate will appear and there is a chemical reaction. If no precipitate is formed, there is no reaction.
Ternary Ionic
Ionic compounds that create more than two elements ex. Na₂ SO₄ (metal/nm) Al(NO₃)₃ KNO₃
Binary Ionic Compound
Ionic compounds that create two elements ex NaCl (metal/nm) AlCl₃
Which of the following types of chemical reactions is illustrated below? KHCO₃(s) → K₂CO₃(s) + H₂O(g) + CO₂(g)
KHCO₃(s) →K₂CO₃(s) + H₂O(g) + CO₂(g) (a) combination (b) *decomposition* (c) single replacement (d) double replacement
Atoms
Made of: - Core electrons: Found close to the nucleus -Valence electrons: Found in the most distant s and p energy subshells. Valence electrons are responsible for holding two or more atoms together in a chemical bond.
Carbonate Decompositions
Metal hydrogen carbonates decompose to give a metal carbonate, water, and carbon dioxide. For example, nickel(II) hydrogen carbonate decomposes as follows: Ni(HCO3)2(s) → NiCO3(s) + H2O(l) + CO2(g) Metal carbonates decompose to give a metal oxide and carbon dioxide gas. For example, calcium carbonate decomposes as follows: CaCO3(s) → CaO(s) + CO2(g)
Activity Series
Metals that are most reactive appear first in the activity series. Metals that are least reactive appear last in the activity series. The relative activity series is: Li > K > Ba > Sr > Ca > Na > Mg > Al > Mn > Zn > Fe > Cd > Co > Ni > Sn > Pb > (H) > Cu > Ag > Hg > Au
Aqueous Acid Displacements
Metals that precede (H) in the activity series react with acids, and those that follow (H) do not react with acids. More active metals react with acid to produce hydrogen gas and an ionic compound. Fe(s) + 2 HCl(aq) → FeCl2(aq) + H2(g) Metals less active than (H) show no reaction. Au(s) + H2SO4(aq) → NR
What is the coefficient of hydrogen gas after balancing the following equation? Mn(s) + H₂SO₄(aq) → MnSO₄(aq) + H₂(g)
Mn(s) + H₂SO₄(aq) → MnSO₄(aq) + H₂(g) a) *1* b) 2 c) 3 d) 4
What is the coefficient of hydrogen gas after balancing the following equation? Mn(s) + H₂SO₄(aq) →MnSO₄(aq) + H₂(g)
Mn(s) + H₂SO₄(aq) →MnSO₄(aq) + H₂(g) (a) *1* (b) 2 (c) 3 (d) 4
How do most nonmetals achieve a noble gas electron configuration?
Most nonmetals achieve a noble gas electron configuration by gaining electrons to become isoelectronic with a noble gas. Chlorine (Group VIIA/17) gains one valence electron and becomes Cl-. A chloride ion has 18 electrons (17 + 1 = 18 e-) and is isoelectronic with argon.
Formation of Anions
Most nonmetals become anions by gaining electrons (Group IVA/14, Group VA/15, Group VIA/16)
Energy
Must supply energy to break a bond regardless of Ionic or Covalent bond
Electron Dot Formula for NH⁴⁺ aka ammonium ion
N has 5 electrons and needs 3 H has 1 electrons and needs 7 N H ⁴⁺ ↓ ↓ ↓ 5 + (4)1 - 1 = 8 electrons (4 pairs) Central Atom is N
9. N2(g) + O2(g) + H2O HNO3(aq)
N2(g) + O2(g) + H2O HNO3(aq)
10. NH4NO3 N2 + O2 + H2O
NH4NO3 N2 + O2 + H2O
Ex of Ionic Bond A + - B -
Na+CL- No sharing. They are giving away electrons.
Delta Notation for Polar Bonds A ẟ+ - B ẟ-
Negatively charged is delta- Positively charged is delta + Used to indicate it like this prior to delta notation
Electronegativity Characteristics
Non-metals gain electrons (metal tend to lose electrons) •Fluorine is the Most electronegative •Oxygen is the second most electronegative
Which of the following types of chemical reactions is illustrated below? N₂(g)+H₂(g)→NH₃(g)
N₂(g)+H₂(g)→NH₃(g) (a) *combination* (b) decomposition (c) single replacement (d) double replacement
Greek naming for binary molecular compounds.
One - mono; Two - di; Three -tri; Four -tetra; Five - penta; hexa; hepta; octa; nona;
Reactions of Nonmetals with Oxygen
Oxygen and a nonmetal react to produce a nonmetal oxide. nonmetal + oxygen gas → nonmetal oxide Sulfur reacts with oxygen to produce sulfur dioxide gas. S(s) + O2(g) → SO2(g)
Electron dot formula for PI₃? aka phosphorus triiodide
P I₃ ↓ ↓ 5 + 3x7 = 26 electrons or 13 pairs
Electron dot formula for PH⁴⁺? aka phosphorus tetrahedral
P is V - Needs 3 H is I - Has 1 to give P H ⁴⁺ ↓ ↓ ↓ 5e + (4)1e -1 = 5e-+4e = 9e- (4 pairs-1) Phosphorus tetrahedral
What is the coefficient of oxygen gas after balancing the following equation? P(s) + O₂(g)→P₂O₃(s),
P(s) + O₂(g)→ P₂O₃(s) (a) 1 (b) 2 (c) *3* (d) 5
Phosphorus pentachloride
PCl₅
Evidence for Chemical Reactions
Release a gas Permanent change in color An insoluble solid is produced (precipate) A heat energy change is observed. ∙ A reaction that releases heat is an exothermic reaction. ∙ A reaction that absorbs heat is an endothermic reaction.
What is the electron dot formula for CO₃²⁻ aka carbonate ion
Resonant structures (3 different scenarios) C O₃ ²⁻ ↓ ↓ ↓ 4 + (3)6 + 2 = 24 electrons (12 pairs) How many electrons 24 How many electron pairs 12
What is the total number of valence electrons in a sulfite ion SO₃²⁻?
S O₃ 2- ↓ ↓ ↓ 6+6*3+2=26
Electron Dot Formula for SO₃ aka sulfur trioxide
S has 6 electrons and needs 2 O has 6 electrons and needs 2 S O ↓ ↓ 6 + (3)6 = 24 electrons (12 pairs) Central Atom is S₁
Sulfur hexabromide
SBr₆
Molecular inorganic compounds
Same as covalent - only 1 kind - both metals ex. CO₂ is binary molecular ammonia - NH₃ methane - CH₄ carbon dioxide - CO₂
Not all ionic compounds are soluble in water. We can use the solubility rules to predict if a compound will be soluble in water.
Solubility Rules All salts of the group I elements (alkali metals = Na, Li, K, Cs, Rb) are soluble. NO3: All nitrates are soluble. Chlorate (ClO3-), perchlorate (ClO4-), and acetate (CH3COO- or C2H3O2-, abbreviated as Oac-) salts are soluble. Cl, Br, I: All chlorides, bromides, and iodides are soluble except those of silver, mercury, and lead (e.g., AgCl, Hg2Cl2, and PbCl2). SO42: Most sulfates are soluble. Exceptions include BaSO4, PbSO4, and SrSO4. CO32: All carbonates are insoluble except NH4+ and those of the Group 1 elements. OH: All hydroxides are insoluble except those of the Group 1 elements, Ba(OH)2, and Sr(OH)2. Ca(OH)2 is slightly soluble. S2: All sulfides are insoluble except those of the Group 1 and Group 2 elements and NH4+
Formation of Cations
The alkali metals (the IA elements) lose a single electron to form a cation with a ¹⁺ charge. The alkaline earth metals (IIA elements) lose two electrons to form a ²⁺ cation. Aluminum, a member of the IIIA family, loses three electrons to form a ³⁺ cation.
Electron Dot Formula for H₂O aka water
₁H ₆O → H₂O ↓ ↓ I VIA (1*2) + 6 = 8 valence electrons [must be eq. #](4 eq. pairs of e-) Locate central atom: H .. O ..H H - O - H (Each - equals 2e-) H : O : H H2(1e)+(1e) = 2 electrons to share O(6e) = 6 electrons to share needs 2 H : O : H (Uses two of the pairs. Need to apply two others.) Octet Rule Oxygen needs 8 electrons and it only has 4 electrons. H : O : H (Uses two of the pairs. Need to apply two others.) H O H Bonding and nonbonding electrons Bonding Electrons Nonbonding electrons or Lone pairs - these still react
Given the electronegativity values of N (3.0) and O (3.5) illustrate the bond polarity in a nitrogen monoxide molecule, NO, using delta notation.
(δ+) N—O (-)
What is the chemical formula for dinitrogen trioxide?
a) N₂O b) *N₂O₃* c) N₂O₄ d) N₂O₅
Given the electronegativity values of H (2.1) and S (2.5) illustrate the bond polarity in a hydrogen sulfide molecule, H₂S, using delta notation
(δ+) H—S (δ-)
Given the values for I (2.5) and Cl (3.0) calculate the electronegativity difference in an iodine monochloride bond, ICl.
0.5
Draw the electron dot formula for ammonia NH₃. How many pairs of nonbonding electrons are in an ammonia molecule?
1
What is the total number of valence electrons in one molecule of H₂O₂? aka hydrogen peroxide
14
Draw the electron dot formula for water H₂O. How many pairs of nonbonding electrons are in a water molecule?
2
Draw the electron dot formula for hydrogen chloride HCl. How many pairs of nonbonding electrons are in a hydrogen chloride molecule? aka Hydrochloric acid
3
What is the total number of valence electrons in one molecule of B₂H₆? aka Diborane
3*2+1*6=12 12 valence electrons
What is the total number of valence electrons in one molecule of P₂O₃? aka diphosphorus trioxide
5*2+6*3 = 28 valence electrons
Draw the electron dot formula for the nitrite ion NO₂⁻. How many pairs of nonbonding electrons are in a nitrite ion?
8
O²⁻
A monoatomic anion. Group VI Oxide ion
What are the products from the following double-replacement reaction? AgNO₃(aq) + Li₃PO₄(aq) →,
AgNO₃(aq) + Li₃PO₄(aq) →, a) Ag₃PO₃ and LiNO₂ b) Ag₃PO₃ and LiNO₃ c) Ag₃PO₄ and LiNO₂ d) *Ag₃PO₄ and LiNO₃*
Which of the following types of chemical reactions is illustrated below? AlCl₃(aq) + AgNO₃(aq) → Al(NO₃)₃(aq) + AgCl(s)
AlCl₃(aq) + AgNO₃(aq) → Al(NO₃)₃(aq) + AgCl(s) a) combination b) decomposition c) single replacement d) *double replacement*
Electron Dot Formulas of Molecules
Also called Lewis structures. Shows the bonds between atoms and helps us visualize the arrangement of electrons.
Balance the following chemical equations. 2. As + NaOH Na3AsO3 + H2
As + NaOH Na3AsO3 + H2
Octet Rule
Atoms bond in a way that each atoms acquires eight electrons in its outer shell. Can achieve the octet rule through: 1. Transfer of electrons from one atom to another. 2. Sharing one or more pairs of electrons.
Gold (III) hydroxide
Au(HO)₃
Draw the electron dot formula for chloroform
CHCl₃. How many pairs of nonbonding electrons are in a chloroform molecule? The large font size element is the central atom., (a) 1 (b) 3 (c) 4 (d) *9*
Carbon has an electronegativity value 2.5. Given the electronegativity of Cl, Br, and I (3.0, 2.8, and 2.5, respectively), which of the following molecules has nonpolar bonds?
CI₄
Electron dot formula for CO₃²⁻? aka carbonate ion
CO₃²⁻ C has 4 valence electrons = 4e O has 6 valence electrons (6)(3)= 18e 22e +2 = 24e (12 pairs) Minus 8e or (4 pair) Distribute remaining 8 pr Or 16 e to satisfy octet
Anions
Formed when an atom gains valence electrons to become negatively charged.
Balance the following chemical equations. 1. SiCl4(l) + H2O(l) SiO2(s) + HCl(aq)
SiCl4(l) + H2O(l) SiO2(s) + HCl(aq)
What is the Bond Length?
The distance between the two atoms is smaller than the sum of their atomic radii and is the bond length. •Takes into account the shared space so it is less than r1+r2
How do main group metals achieve a noble gas electron configuration?
They achieve a noble gas electron configuration by losing their valence electrons, and are isoelectronic with a noble gas. o Magnesium (Group IIA/2) loses its two valence electrons to become Mg²⁺ o A magnesium ion has 10 electrons (12 - 2 = 10 e-) and is isoelectronic with neon.
Binary acid:
Two elements (hydrogen and and one other nonmetal) (ex.): HF - Hydrofluoric acid HCl - Hydrochloric acid HBr - Hydrobromic acid HI - Hydroiodic acid H₂S -Hydrosulfuric acid
4. V2O5 + HCl VOCl3 + H2O
V2O5 + HCl VOCl3 + H2O
Activity Series Concept
When a metal undergoes a replacement reaction, it displaces another metal from a compound or aqueous solution. The metal that displaces the other metal does so because it is more active. The activity of a metal is a measure of its ability to compete in a replacement reaction. In an activity series, a sequence of metals is arranged according to its ability to undergo a reaction.
Polyatomic anion
a group of atoms bound together that has an overall charge is called ?
Given the electronegativity values of N (3.0) and O (3.5), illustrate the bond polarity in a nitrogen monoxide molecule, NO, using delta notation.,
a) (δ+) N—O (δ+) *b) (δ+) N—O (δ-)* c) (δ-) N—O (δ+) d) (δ-) N—O (δ-)
Draw the electron dot formula for ammonia, NH₃. How many pairs of nonbonding electrons are in an ammonia molecule?
a) *1* b) 2 c) 3 d) 6
What is the chemical formula for hydrobromic acid?
a) *HBr(aq)* b) HBrO(aq) c) HBrO₂(aq) d) HBrO₃(aq)
What are the products from the following single-replacement reaction? Al(s) + Pb(NO₃)₂(aq) →
a) *Pb and Al(NO₃)₃* b) Pb and Al(NO₂)₃ c) PbO and Al(NO₃)₃ d) PbO and Al(NO₂)₃
What is the molecular shape of a hydrogen sulfide molecule H₂S?
a) *bent* b) linear c) tetrahedral d) trigonal pyramidal
What is the total number of valence electrons in one molecule of P₂O₃?
a) 2 b) 11 c) 18 d) *28*
Which of the following metals reacts with water at room temperature?
a) Ba b) Ca c) *Na* d) all of the above
What is the chemical formula for the hydrogen carbonate ion?
a) C₂H₃O₂- b) C₂H₃O₂²⁻ c) *HCO₃⁻* d) HCO₃²⁻
What is the chemical formula for iron(III) sulfate?
a) FeSO₃ b) FeSO₄ c) Fe₂(SO₃)₃ d) *Fe₂(SO₄)₃*
What is the chemical formula for strontium iodide?
a) SrI b) *SrI₂* c) SrI₃ d) Sr₃I₂
Al(OH)₃
aluminum hydroxide
(NH₄)₂SO₄
ammonium sulfate
What is the molecular shape of a hydrogen sulfide molecule, H₂S?
bent
CuCN
copper (I) cyanide
Ex of Covalent Bond A-A
ex. H-H, C-H, C-I Both share equally 50% - 50% This is called a non-polar covalent bond
Which noble gas is isoelectronic with a lithium ion?
helium
What is the term for an attraction between a hydrogen atom bonded to a highly electronegative atom (O, N or F) and a nonbonding electron pair on a highly electronegative atom in another molecule?
hydrogen bond
HF
hydrogen fluoride
HNO₂
hydrogen nitrite
Which of the following is a general trend for the electronegativity of elements in the periodic table?
increases from left to right increases from bottom to top
What is the electron pair geometry for a silicon dioxide molecule SiO₂?
linear
What is the molecular shape of a silicon dioxide molecule SiO₂?
linear
N₁O₅
nitrogren pentoxide
Se₂Cl₄
selenium (II) tetrachloride
What type of bond is characterized by sharing one pair of electrons?
single bond
What is the electron pair geometry for a methane molecule CH₄?
tetrahedral
What is the electron pair geometry for a phosphine molecule PH₃?
tetrahedral
What is the electron pair geometry for a silane molecule SiH₄?
tetrahedral
What is the electron pair geometry for a water molecule H₂O?
tetrahedral
What is the electron pair geometry for an ammonia molecule NH₃?
tetrahedral
What is the molecular shape of a methane molecule CH₄?
tetrahedral
What is the molecular shape of a silane molecule SiH₄?
tetrahedral
Ternary oxyacids are aqueous solutions of a compound containing hydrogen and an oxyanion. If the acid is derived from an oxyanion ending in -ate
the suffix is changed to -ic acid., ex. HNO3 (aq) is nitric acid (from NO3-, nitrate ion)
If the acid is derived from an oxyanion ending in -ite
the suffix is changed to -ous acid., HNO2 (aq) is nitrous acid (from NO2-, nitrite ion).
Which of the following solid compounds is insoluble in water?
(a) (NH₄)₂CO₃ (b) K₂CrO₄ (c) *BaSO₄* (d) Na₂S
Draw the structural formula for fluorine F₂, and state the type of bond in a fluorine molecule.,
(a) *1 single bond* (b) 1 double bond (c) 1 triple bond (d) 1 hydrogen bond
Draw the structural formula for phosphorus triiodide PI₃, and state the type of bonds in a phosphorus triiodide molecule.
(a) *3 single bonds* (b) 3 double bonds (c) 1 single bond and 2 double bonds (d) 2 single bonds and 1 double bond
What is the predicted ionic charge for a Bi ion?
(a) *3+* (b) 3- (c) 4+ (d) 4-
What is the chemical formula for iron(II) sulfite?
(a) *FeSO₃* (b) FeSO₄ (c) Fe₂(SO₃)₃ (d) Fe₂(SO₄)₃
Which of the following is evidence for a chemical reaction?
(a) a gas is detected (b) a precipitate is formed (c) a flame is observed (d) *all of the above*
What is the term for a substance that speeds up a reaction without being permanently changed?
(a) accelerator (b) *catalyst* (c) inhibitor (d) reactant
What is the systematic name for aqueous H₂CO₃?
(a) acetic acid (b) *carbonic acid* (c) dicarbonic acid (d) hydrogen carbonic acid
What is the electron pair geometry for a water molecule H₂O? The large font size element is the central atom.,
(a) bent (b) linear (c) *tetrahedral* (d) trigonal pyramidal
What is the electron pair geometry for a carbonate ion CO₃²-?
(a) bent (b) linear (c) tetrahedral (d) *trigonal planar*
What is the molecular shape of a carbonate ion CO₃²⁻?
(a) bent (b) linear (c) tetrahedral (d) *trigonal planar*
What is the systematic name for SF₆?
(a) sulfur tetrafluoride (b) *sulfur hexafluoride* (c) sulfur heptafluoride (d) sulfur octafluoride
Guidelines for Electron Dot Formulas
1. Calculate the total number of valence electrons by adding all of the valence electrons for each atom in the molecule. 2. Divide the total valence electrons by 2 to find the number of electron pairs. 3. Surround the central atom with four electron pairs. Use the remaining electron pairs to complete the octet around the other atoms. The only exception is hydrogen with only needs two electrons. 4. Electron pairs that are shared by atoms are called BONDING ELECTRONS. The other electrons complete octets and are called NONBONDING ELECTRONS or LONE PAIRS. 5. If there are not enough electron pairs to provide each atom with an octet, move a nonbonding electron pair between two atoms that already share an electron pair. Note: ASSUME ALL H ATOMS ARE NON METALS UNLESS NOTED
A combination reaction is ____?
A combination reaction is a reaction in which two simpler substances are combined into a more complex compound. Combination reactions are also called synthesis reactions. We will look at three combination reactions: The reaction of a metal with oxygen The reaction of a nonmetal with oxygen The reaction of a metal and a nonmetal
Active Metals
A few metals are active enough to react directly with water. These are called active metals. The active metals are Li, Na, K, Rb, Cs, Ca, Sr, and Ba. They react with water to produce a metal hydroxide and hydrogen gas. 2 Na(s) + 2 H2O(l) → 2 NaOH(aq) + H2(g) Ca(s) + 2 H2O(l) → Ca(OH)2(aq) + H2(g)
A chemical equation describes a chemical reaction using formulas and symbols.
A general chemical equation is as follows: A + B → C + D In this equation, A and B are reactants and C and D are products.
N³⁻
A monoatomic anion. Group VII Nitride ion
Which of the following types of chemical reactions is illustrated below? AlCl₃(aq)+AgNO₃(aq)→ Al(NO₃)₃(aq) + AgCl(s)
AlCl₃(aq)+AgNO₃(aq)→ Al(NO₃)₃(aq) + AgCl(s) (a) combination (b) decomposition (c) single replacement (d) *double replacement*
Electron dot formula for the following: N₂ aka Dinitrogen
Always will be diatomic. You will never find Nitrogen alone. Triple bonds are very strong. It is one of the strongest bonds. N₂ 5e x 2 = 10 electrons or 5 election pairs
Which of the following statements are true regarding an ionic bond between aluminum and nitrogen in an AlN formula unit? a) Aluminum and nitrogen ions bond by covalent attractions. b) Aluminum atoms lose electrons and nitrogen atoms gain electrons. c) The ionic radius of an aluminum ion is less than its atomic radius. d) Breaking an ionic bond between aluminum and nitrogen releases energy.
Answers: a) False (Ionic because it has metal) b) True (Metals lose/Nonmetals gain) c) True (Al is a Cation) d) True (Breaking an ionic bond releases energy)
Which of the following statements are true regarding a covalent bond between carbon and oxygen? ₆C ₈O Covalent Bond ₆C→1s²2s²2p² (4e) ₈O →1s²2s²2p⁴ (6e)
Answers: a) False (They are shared it is covalent) b) False (They are in a specific region shared space) c) True (The shared atoms are smaller than the two wholes because they overlap) d) F (Must supply energy to break a bond)²
Predict whether each of the following is held together by ionic or covalent bonds a) zinc bromide, ZnBr₂ b) carbon dioxide, CO₂ c) iodine heptafluoride, IF₇ d) lead (II) sulfate, PbSO₄
Answers: a) Ionic Bond - Metal/NM b) Covalent Bond - NM/NM c) Covalent Bond - NM/NM d) Ionic Bond - Metal/NM
What is the coefficient of KNO₃ after balancing the following equation? Au(NO₃)₃(aq) + K₂CrO₄(aq) → Au₂(CrO₄)₃(s) + KNO₃(aq)
Au(NO₃)₃(aq) + K₂CrO₄(aq) → Au₂(CrO₄)₃(s) + KNO₃(aq) (a) 1 (b) 2 (c) 3 (d) *6*
Electronegativity increases
From the bottom to the top From the left to the right side
Electron dot formula for SeO₃²⁻? aka selenite ion
SeO₃²⁻ Se is from family 6 needs 2 more = 6e O is from family 6 needs 2 more = 18e 24 electrons (12 pairs) +2 (1 pair) 26 divided by 8= 3 so we have 2 left over which goes over Se 26 - 2 dots over Se =24 (12 pairs) 24 (12 pair) - 6 (3 pairs) =18 (9 pairs) All four are satisfied: only create double and triple bonds when the octet rule is satisfied
6. SiO2 + HF SiF4 + H2O
SiO2 + HF SiF4 + H2O
*Difference in electronegativity* - To determine whether it is a polar or non polar covalent bond
Subtract the negativity values. •If the answer is less than 0.5 or greater it is a polar covalent bond. •If the answer is 0.49 or less it is a nonpolar covalent bond
In combination reactions, two or more smaller molecules are combined into a more complex molecule. In a decomposition reaction, a molecule breaks apart into two or more simpler molecules. In a single-replacement reaction, a more active metal displaces a less active metal according to the activity series. In a double-replacement reaction, two aqueous solutions produce a precipitate of an insoluble compound. The insoluble compound can be predicted based on the solubility rules. In a neutralization reaction, an acid and a base react to produce a salt and water.
Summary of the five reactions.
Bent Molecules Ex. H₂O Has 8 v.e. or 4 pairs 2 bonding pairs and 2 red lone pairs Or 2/2 104.4°
The central atom is surrounded by two bonding pairs and two non bonding pairs (lone pair). Geometry: Tetrahedral Molecular shape: Bent
Ionic Radii
The radius of a cation is smaller than the radius of its starting atom. •Because it is losing the outer shell (electrons) •The radius of an anion is larger than the radius of its starting atom. •Because it is filling the outer shell.
What is the term for a model that explains the shapes of molecules based upon electron pair repulsion about the central atom?
VSEPR theory
Classification of chemical reactions
We can place chemical reactions into five categories: ∙Combination reactions ∙Decomposition reactions ∙Single-replacement reactions ∙Double-replacement reactions ∙Neutralization reactions
Which of the following solid compounds is insoluble in water?
a) Li₂CO₃ b) AgC₂H₃O₂ c) Cu(NO₃)₂ d) *all of the above* e) none of the above
40. Which of the following metals does not react with aqueous Ni(NO₃)₂? Partial Activity Series: Mg > Al > Ni > (H) > Cu
a) Mg b) Al c) *Cu* d) all of the above
According to the general trends in the periodic table which of the following is the most electronegative element?
a) N b) O c) S d) *F*
What is the chemical formula for the compound composed of Na+ and CO₃²⁻ ions?
a) NaCO₃ b) *Na₂CO₃* c) Na(CO₃)₂ d) Na₂(CO₃)₂
What is the chemical formula for zinc hydroxide?
a) Zn₃OH b) *Zn(OH)₂* c) Zn(OH)₃ d) Zn₃(OH)₂
Which of the following is evidence for a chemical reaction?
a) a gas is detected b) a precipitate is formed c) a flame is observed d) *all of the above*
Which noble gas is isoelectronic with a sulfide ion?
a) helium b) neon c) *argon* d) krypton
What is the systematic name for aqueous H₃PO₃?
a) hydrophosphoric acid b) hydrophosphorous acid c) phosphorous acid d) *phosphoric acid*
What is the name for N₃-?
a) nitrogen ion b) *nitride ion* c) nitrite ion d) nitrate ion
What is the name for P₄O₁₀?
a) phosphorus oxide b) phosphorus decaoxide c) *tetraphosphorus decaoxide* d) tetraphosphorus nonaoxide
What is the ionic charge for the copper ion in Cu₂S?
a) zero b) *1+* c) 2+ d) 3+
What is the electron pair geometry for a carbonate ion CO₃²⁻?
trigonal planar
What is the electron pair geometry for a phosgene molecule COCl₂?
trigonal planar
What is the molecular shape of a carbonate ion CO₃²⁻?
trigonal planar
What is the molecular shape of a phosgene molecule COCl₂?
trigonal planar
What is the molecular shape of a phosphine molecule, PH₃?
trigonal pyramidal
What type of bond is characterized by sharing three pairs of electrons?
triple bond
Predict which of the following is connected by an ionic bond.
(a) HI (b) IBr (c) *LiH* (d) all of the above
When we balance a ________ equation, the number of each type of atom must be the same on both the product and reactant sides of the equation. We use coefficients in
When we balance a chemical equation, the number of each type of atom must be the same on both the product and reactant sides of the equation. We use coefficients in front of compounds to balance chemical reactions.
7. Zn + HCl ZnCl2 + H2
Zn + HCl ZnCl2 + H2
Which of the following types of chemical reactions is illustrated below? Zn(s) + HCl(aq) → ZnCl₂(aq) + H₂(g)
Zn(s) + HCl(aq) → ZnCl₂(aq) + H₂(g) a) combination b) decomposition c) *single replacement* d) double replacement
What is the coefficient of water after balancing the following equation? _H₃PO₄(aq) + _Ba(OH)₂(aq) → _Ba₃(PO₄)₂(s) + _H₂O(l)
_H₃PO₄(aq) + _Ba(OH)₂(aq) → _Ba₃(PO₄)₂(s) + _H₂O(l) (a) 1 (b) 2 (c) 3 (d) *6*
What is the coefficient of carbon dioxide after balancing the following equation? _KHCO₃(s)→_K₂CO₃(s) + _H₂O(g) +_CO₂(g)
_KHCO₃(s)→ _K₂CO₃(s) + _H₂O(g) +_CO₂(g) (a) *1* (b) 2 (c) 3 (d) 4
What is the coefficient of water after balancing the following equation? _Li(s) + _H₂O(l) → _LiOH(aq) + _H₂(g)
_Li(s) + _H₂O(l) → _LiOH(aq) + _H₂(g) (a) 1 (b) *2* (c) 3 (d) 4
What is the coefficient of phosphorus after balancing the following equation? _P(s) +_O₂(g)→ P₂O₅(s)
_P(s) +_O₂(g)→ P₂O₅(s) (a) 1 (b) 2 (c) *4* (d) 5
What is the coefficient of oxygen gas after balancing the following equation? _P(s)+_O₂(g)→_P₂O₅(s)
_P(s)+_O₂(g)→_P₂O₅(s) (a) 1 (b) 2 (c) 4 (d) *5*
What is the chemical formula for hydrobromic acid?
(a) *HBr(aq)* (b) HBrO(aq) (c) HBrO₂(aq) (d) HBrO₃(aq)
What is the chemical formula for potassium cyanide?
(a) *KCN* (b) K₂CN (c) K(CN)₂ (d) K₃CN
What is the chemical formula for magnesium carbonate?
(a) *MgCO₃* (b) Mg(CrO₃)₂ (c) Mg₂CO₃ (d) Mg₃(CO₃)₂
Are BaSO4 and KCl the products from the following double-replacement reaction? BaCl₂(aq) + K₂SO₄(aq) → BaSO₄ + 2KCl
(a) *Yes* (b) No
Will the following double-replacement reaction take place? AgNO₃(aq) + NaCl(aq) → AgCl + NaNO₃
(a) *Yes* (b) No
What is the general term for any negatively charged ion?
(a) *anion* (b) cation (c) monoatomic ion (d) polyatomic ion
What is the molecular shape of a water molecule H₂O? The large font size element is the central atom.,
(a) *bent* (b) linear (c) tetrahedral (d) trigonal pyramidal
Given the values for N (3.0) and O (3.5) calculate the electronegativity difference in a nitrogen monoxide bond, NO.,
(a) -0.5 (b) -6.5 (c) *0.5* (d) 6.5
Draw the electron dot formula for chloroform CHCl₃. How many pairs of nonbonding electrons are in a chloroform molecule? The large font sized carbon is the central atom.
(a) 1 (b) 3 (c) 4 (d) *9*
What is the total number of valence electrons in one molecule of S₂Cl₂?
(a) 13 (b) 18 (c) 20 (d) *26*
What is the total number of valence electrons in one molecule of P₂O₃?
(a) 2 (b) 11 (c) 18 (d) *28*
What is the total number of valence electrons in a sulfite ion SO₃²⁻?
(a) 22 (b) 24 (c) *26* (d) 34
What is the predicted ionic charge of an element in Group VIA/16?
(a) 2⁺ (b) 6⁺ (c) *2⁻* (d) 6⁻
How many valence electrons are in a phosphorus atom and a phosphide ion?
(a) 3 and 8, respectively (b) *5 and 8, respectively* (c) 8 and 5, respectively (d) 15 and 18, respectively
What is the chemical formula for silver oxide?
(a) AgO (b) AgO₂ (c) *Ag₂O* (d) Ag₂O₃
Which of the following metals reacts with water at room temperature?
(a) Al (b) Sr (c) Fe (d) *Mg*
According to the general trends in the periodic table which of the following is the most electronegative element?
(a) Ar (b) *Cl* (c) S (d) P
What is the chemical formula for cobalt(II) bromide?
(a) Co₂Br (b) *CoBr₂* (c) Co₃Br₂ (d) Co₂Br₃
What is the chemical formula for iron(III) sulfate?
(a) FeSO₃ (b) FeSO₄ (c) Fe₂(SO₃)₃ (d) *Fe₂(SO₄)₃*
According to the general trends in the periodic table which of the following is the most electronegative element?
(a) H (b) *F* (c) Cl (d) Br
What is the chemical formula for nitric acid?
(a) HNO₂(aq) (b) *HNO₃(aq)* (c) H₂NO₂(aq) (d) H₂NO₃(aq)
What is the chemical formula for sulfurous acid?
(a) HSO₃(aq) (b) HSO₄(aq) (c) *H₂SO₃(aq)* (d) H₂SO⁴(aq)
What is the chemical formula for iodine heptafluoride?
(a) IF (b) IF₆ (c) *IF⁷* (d) I₂F₆
Which of the following metals does not react with aqueous Ni(NO₃)₂? Partial Activity Series: Mg > Al > Ni > (H) > Cu
(a) Mg (b) Al (c) *Cu* (d) all of the above
What is the chemical formula for laughing gas - dinitrogen monooxide?
(a) NO (b) N₂O₂ (c) *N₂O* (d) NO₂
What is the chemical formula for the ternary compound composed of Na+ and CO₃²⁻ ions?
(a) NaCO₃ (b) Na₂CO₃ (c) *Na(CO₃)₂* (d) Na₂(CO₃)₂
What are the products from the complete neutralization of sulfuric acid with aqueous sodium hydroxide?
(a) NaHSO₃(aq) and H₂O(l) (b) NaHSO⁴(aq) and H₂O(l) (c) Na₂SO₃(aq) and H₂O(l) (d) *Na₂SO₄(aq) and H₂O(l)*
According to the general trends in the periodic table which of the following is the most electronegative element?
(a) Ne (b) *O* (c) S (d) Se
Which of the following solid compounds is soluble in water?
(a) NiCO₃ (b) PbCrO₄ (c) Ag₃PO₄ (d) *Ba(OH)₂*
What is the chemical formula for dinitrogen pentaoxide?
(a) N₂O (b) N₂O₃ (c) N₂O₄ (d) *N₂O₅*
What is the chemical formula for dinitrogen trioxide?
(a) N₂O (b) *N₂O₃* (c) N₂O₄ (d) N₂O₅
What is the chemical formula for tetraphosphorus trisulfide (the flammable compound on match tips that causes ignition)?
(a) PS₃ (b) P₄S (c) P₃S₄ (d) *P₄S₃*
What is the chemical formula for the binary compound composed of Sr²⁺ and Br⁻ ions?
(a) SrBr (b) Sr₂Br (c) *SrBr₂* (d) Sr₂Br₂
Given the electronegativity values of C (2.5), N (3.0), O (3.5), and S (2.5), which of the following molecules have polar bonds?
(a) carbon dioxide, CO₂ (b) sulfur dioxide, SO₂ (c) smog, NO₂ (d) *all of the above*
What is the strongest intermolecular force in water containing molecules with H-O bonds?
(a) covalent bonds (b) dipole forces (c) dispersion forces (d) *hydrogen bonds*
What is the term for an attraction between a hydrogen atom bonded to a highly electronegative atom (O, N, or F), and a nonbonding electron pair on a highly electronegative atom in another molecule?,
(a) dipole force (b) dispersion force (c) *hydrogen bond* (d) intermolecular bond
Which noble gas is isoelectronic with a calcium ion?
(a) helium (b) neon (c) *argon* (d) krypton
Given the electronegativity values of H (2.1) N (3.0), and O (3.5), which of the following molecules have polar bonds?
(a) water, H₂O (b) ammonia, NH₃ (c) laughing gas, N₂O (d)*all of the above*
What is the ionic charge for the lead ion in PbO₂?
(a) zero (b) 1+ (c) 2+ (d) *4+*
What is the ionic charge for the cobalt ion in Co₃N₂?
(a) zero (b) 1+ (c) *2+* (d) 3+
What is the ionic charge for the nickel ion in NiCO₃?
(a) zero (b) 1+ (c) *2+* (d) 3+
Given the electronegativity values of Br (2.8) and F (4.0) illustrate the bond polarity in a bromine monofluoride molecule, BrF, using delta notation.,
(a)(δ+) Br—F (δ+) (b)*(δ+) Br—F (δ-)* (c)(δ-) Br—F (δ+) (d)(δ-) Br—F (δ-)
Given the electronegativity values of C (2.5) and O (3.5) illustrate the bond polarity in a carbon monoxide molecule, CO, using delta notation
(δ+) C—O (δ-)
Given the electronegativity values of H (2.1) and N (3.0) illustrate the bond polarity in an ammonia molecule, NH₃, using delta notation.
(δ-) N—H (δ+)
Polar Covalent Bonds
*Covalent Bonds* - Result from sharing of valence electrons. - Often times two atoms do not share the electrons equally. That is one of the atoms hold onto the electrons more tightly than the other. When one of the atoms holds that shared electrons more tightly the bond is polarized - Polar Covalent bond - Covalent bond where the electrons are not shared equally
Type of Bonds
*Ionic Bond*: Formed when a complete transfer of electrons between atoms occurs forming ionic compounds. *Covalent Bond*: Formed when two atoms share electrons to form molecular compounds.
Classification of ions - Cations 1. Monoatomic 2. Polyatomic - Anions 1. Monoatomic 2. Polyatomic
- Cations + charged ions metals form cations - Anions charged ions non metals form anions
Monoatomic cations (lose 1 electron)
- Metal atoms can lose valence electrons and become positively charged. Cations are named for the parent atom followed by the word ion ex. Na⁺ is sodium ion Al³⁺ is aluminum ion This rule applies for metals that usually form one ion. Primary Group I. This includes the main group metals except: - tin (Sn⁴⁺, Sn²⁺) - lead (Pb⁴⁺, Pb²⁺) - Ag⁺ - Zn²⁺ - Cd²⁺
Predict whether each of the following is held together by ionic or covalent bonds. a) aluminum chloride, AlCl₃ b) water H₂O c) sulfur trioxide, SO₃ d) iron (II) sulfate, FeSO₄
Answers: a) Ionic Bond - Metal/Nonmetal b) Covalent Bond - NM so No Ionic Bond c) Covalent Bond - NM/NM d) Ionic Bond - Metal/NM
HC2H3O2(aq) + NaHCO3(s) → NaC2H3O2(aq) + H2O(l) + CO2(g) The equation can be read as follows:
Aqueous acetic acid is added to solid sodium carbonate and yields aqueous sodium acetate, liquid water, and carbon dioxide gas.
Double replacement part 2
Aqueous barium chloride reacts with aqueous potassium chromate as follows: 2 BaCl2(aq) + K2CrO4(aq) → BaCrO4(s) + 2 KCl(aq) From the solubility rules, BaCrO4 is insoluble, so there is a double-replacement reaction. Aqueous sodium chloride reacts with aqueous lithium nitrate as follows: NaCl(aq) + LiNO3(aq) → NaNO3(aq) + LiCl(aq) Both NaNO3 and LiCl are soluble, so there is no reaction
Linear Molecules Ex. CO₂ Has 16 v.e. or 8 pairs Double Bonds Or 4/0 180°
The central atom is surrounded by two double bonds. Geometry: Linear Molecular shape: Linear
You can quickly verify that the chemical formula is written correctly by crossing over the charge on each ion.
The charge on the aluminum ion becomes the subscript for the oxygen, and the charge on the oxide ion becomes the subscript for the aluminum ion.
Reactions of Metals with Oxygen
When a metal is heated with oxygen gas, a metal oxide is produced. metal + oxygen gas → metal oxide ex.
Chapter Summary:
•Chemical bonds hold atoms together in molecules. •Atoms bond in such a way as to have eight electrons in their valence shell. This is called the octet rule. •There are two types of bonds: ionic and covalent. •Ionic bonds are formed between a cation and an anion. •Covalent bonds are formed from the sharing of electrons. •Electron dot formulas help us visualize the arrangements of atoms in a molecule. •Electrons are shared unequally in polar covalent bonds. • Electronegativity is a measure of the ability of an atom to attract electrons in a chemical bond. • Electronegativity increases from left to right and from bottom to top on the periodic table. •VSEPR theory can be used to predict the shapes of molecules. •The electron pair geometry indicates the arrangement of bonding and nonbonding pairs around a central atom. •The molecular shape indicates the arrangement of atoms in a molecule.
