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5.E: Exercises

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    357321
    • Anonymous
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    5.2: Chemical Formulas

    1. Classify each of the following as an atomic element, a molecular element, an ionic compound, or a molecular compound. State how many atoms are in each formula unit or molecule.
      1. Fe
      2. PCl3
      3. P4
      4. CaBr2
    Answer
    1. atomic element
    2. molecular compound, 4 atoms
    3. molecular element, 4 atoms
    4. ionic compound, 3 atoms

     

    1. Classify each of the following as an atomic element, a molecular element, an ionic compound, or a molecular compound. State how many atoms are in each formula unit or molecule.
      1. I2
      2. Fe(NO3)2
      3. H2O
      4. Al
    Answer
    1. molecular element, 2 atoms
    2. ionic compound, 9 atoms
    3. molecular compound, 3 atoms
    4. atomic element

     

    1. What is the difference between CO and Co?
    Answer

    CO is a molecular compound containing carbon and oxygen. Co is the atomic element cobalt.

     

    1. What is the difference between H2O and H2O2 (hydrogen peroxide)?
    Answer

    H2O has two hydrogen atoms and one oxygen atom. H2O2 has two hydrogen atoms and two oxygen atoms.

     

    1. Explain why the formula for an atom of the element oxygen and the formula for a molecule of oxygen differ.
    Answer

    The symbol for the element oxygen, O, represents both the element and one atom of oxygen. A molecule of oxygen, O2, contains two oxygen atoms; the subscript 2 in the formula must be used to distinguish the diatomic molecule from two single oxygen atoms.

     

    1. Write the molecular and empirical formulas of the following compounds:
      1. Figure A shows a carbon atom that forms two, separate double bonds with two oxygen atoms.
      2. Figure B shows a hydrogen atom which forms a single bond with a carbon atom. The carbon atom forms a triple bond with another carbon atom. The second carbon atom forms a single bond with a hydrogen atom.
      3. Figure C shows a carbon atom forming a double bond with another carbon atom. Each carbon atom forms a single bond with two hydrogen atoms.
      4. Figure D shows a sulfur atom forming single bonds with four oxygen atoms. Two of the oxygen atoms form a single bond with a hydrogen atom.
    Answer
    1. molecular = CO2, empirical = CO2
    2. molecular = C2H2, empirical = CH
    3. molecular = C2H4, empirical = CH2
    4. molecular = H2SO4, empirical = H2SO4

     

    1. Write the molecular and empirical formulas of the following compounds:
      1. Figure A shows a structural diagram of four carbon atoms bonded together into a chain. The two carbon atoms on the left form a double bond with each other. All of the remaining carbon atoms form single bonds with each other. The leftmost carbon also forms single bonds with two hydrogen. The second carbon in the chain forms a single bond with a hydrogen atom. The third carbon in the chain forms a single bond with two hydrogen atoms each. The rightmost carbon forms a single bond with three hydrogen atoms each.
      2. Figure B shows a structural diagram of a molecule that has a chain of four carbon atoms. The leftmost carbon atom forms a single bond with three hydrogen atoms each and single bond with the second carbon atom. The second carbon atom forms a triple bond with the third carbon atom. The third carbon atom forms a single bond to the fourth carbon atom. The fourth carbon atom forms a single bond to three hydrogen atoms each.
      3. Figure C shows a structural diagram of two silicon atoms are bonded together with a single bond. Each of the silicon atoms form single bonds to two chlorine atoms each and one hydrogen atom.
      4. Figure D shows a structural diagram of a phosphorus atom that forms a single bond to four oxygen atoms each. Three of the oxygen atoms each have a single bond to a hydrogen atom.
    Answer
    1. molecular = C4H8; empirical = CH2
    2. molecular = C4H6; empirical = C2H3
    3. molecular = Si2H2Cl4; empirical = SiHCl2
    4. molecular = H3PO4; empirical = H3PO4

     

    1. Determine the empirical formulas for the following compounds:
      1. caffeine, C8H10N4O2
      2. sucrose, C12H22O11
      3. hydrogen peroxide, H2O2
      4. glucose, C6H12O6
      5. ascorbic acid (vitamin C), C6H8O6
    Answer
    1. C4H5N2O
    2. C12H22O11
    3. HO
    4. CH2O
    5. C3H4O3

     

    1. Write the empirical formulas for the following compounds:
      1. Figure A shows a structural diagram of two carbon atoms that form a single bond with each other. The left carbon atom forms single bonds with hydrogen atoms each. The right carbon forms a double bond to an oxygen atom. The right carbon also forms a single bonded to another oxygen atom. This oxygen atom also forms a single bond to a hydrogen atom.
      2. Figure B shows a structural diagram containing a leftmost carbon that forms single bonds to three hydrogen atoms each. This leftmost carbon also forms a single bond to a second carbon atom. The second carbon atom forms a double bond with an oxygen atom. The second carbon also forms a single bond to a second oxygen atom. This oxygen atom forms a single bond to a third carbon atom. This third carbon atom forms single bonds with two hydrogen atoms each as well as a single bond with another carbon atom. The rightmost carbon atom forms a single bond with three hydrogen atoms each.
    Answer
    1. CH2O
    2. C2H4O

     

    1. Determine the empirical formulas for the following compounds:
      1. acetic acid, C2H4O2
      2. citric acid, C6H8O7
      3. hydrazine, N2H4
      4. nicotine, C10H14N2
      5. butane, C4H10
    Answer
    1. CH2O
    2. C6H8O7
    3. NH2
    4. C5H7N
    5. C2H5

     

    5.3: A Closer Look at Elements and Compounds

    1. From their positions on the periodic table, will Cu and I form a molecular compound or an ionic compound?
    Answer

    ionic compound

     

    1. From their positions on the periodic table, will N and S form a molecular compound or an ionic compound?
    Answer

    molecular compound

     

    1. Using the periodic table, predict whether the following chlorides are ionic or covalent: KCl, NCl3, ICl, MgCl2, PCl5, and CCl4.
    Answer

    ionic = KCl, MgCl2; covalent = ICl, PCl5, CCl4

     

    1. Using the periodic table, predict whether the following chlorides are ionic or covalent: SiCl4, PCl3, CaCl2, CsCl, CuCl2, and CrCl3.
    Answer

    ionic = CaCl2, CsCl, CuCl2, CrCl3; covalent = SiCl4, PCl3

     

    5.4: Chemical Nomenclature and the Classification of Compounds

    1. Classify each of the following compounds as binary ionic, ionic containing polyatomic ions, binary molecular, binary acid, or oxyacid.
      1. NF3
      2. HI
      3. (NH4)2CO3
      4. Sr3(PO4)2
      5. BaO
      6. H2SO4
    Answer
    1. binary molecular
    2. binary acid
    3. ionic containing polyatomic ions
    4. ionic containing polyatomic ions
    5. binary ionic
    6. oxyacid

     

    1. Classify each of the following compounds as binary ionic, ionic containing polyatomic ions, binary molecular, binary acid, or oxyacid.
      1. HClO3
      2. Mg(C2H3O2)2
      3. H2S
      4. Ag2S
      5. N2Cl4
      6. CoBr2
    Answer
    1. oxyacid
    2. ionic containing polyatomic ions
    3. binary acid
    4. binary ionic
    5. binary molecular
    6. binary ionic

     

    5.5: Binary Ionic Compounds

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Mg2+ and Cl
      2. Na+ and O2−
      3. Cd2+ and O2−
    Answer
    1. MgCl2, magnesium chloride
    2. Na2O, sodium oxide
    3. CdO, cadmium oxide

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. K+ and S2−
      2. Ag+ and Br
      3. Sr2+ and N3−
    Answer
    1. K2S, potassium sulfide
    2. AgBr, silver bromide
    3. Sr3N2, strontium nitride

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Zn2+ and F
      2. Ca2+ and O2−
      3. Li+ and P3−
    Answer
    1. ZnF2, zinc fluoride
    2. CaO, calcium oxide
    3. Li3P, lithium phosphide

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Na+ and N3−
      2. Sr2+ and I
      3. Al3+ and S2−
    Answer
    1. Na3N, sodium nitride
    2. SrI2, strontium iodide
    3. Al2S3, aluminum sulfide

     

    5.6: Ions With Variable Charges

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Ni2+ and Cl
      2. Fe2+ and O2−
      3. Fe3+ and O2−
    Answer
    1. NiCl2, nickel(II) chloride
    2. FeO, iron(II) oxide
    3. Fe2O3, iron(III) oxide

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Cu+ and S2−
      2. Pt2+ and Br
      3. Cr2+ and N3−
    Answer
    1. Cu2S, copper(I) sulfide
    2. PtBr2, platinum(II) bromide
    3. Cr3N2, chromium(II) nitride

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Cu2+ and F
      2. U6+ and O2−
      3. Au+ and P3−
    Answer
    1. CuF2, copper(II) fluoride
    2. UO3, uranium(VI) oxide
    3. Au3P, gold(I) phosphide

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Sn2+ and N3−
      2. Co2+ and I
      3. Au3+ and S2−
    Answer
    1. Sn3N2, tin(II) nitride
    2. CoI2, cobalt(II) iodide
    3. Au2S3, gold(III) sulfide

     

    1. Name each of the following compounds:
      1. Cr2O3
      2. FeCl2
      3. CrO3
      4. TiCl4
      5. CoO
      6. SnS2
    Answer
    1. chromium(III) oxide
    2. iron(II) chloride
    3. chromium(VI) oxide
    4. titanium(IV) chloride
    5. cobalt(II) oxide
    6. tin(IV) sulfide

     

    1. Name each of the following compounds:
      1. NiBr2
      2. WO3
      3. CoS
      4. V2O5
      5. MnO2
      6. Fe2O3
    Answer
    1. nickel(II) bromide
    2. tungsten(VI) oxide
    3. cobalt(II) sulfide
    4. vanadium(V) oxide
    5. manganese(IV) oxide
    6. iron(III) oxide

     

    5.7: Ionic Compounds Containing Polyatomic Ions

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. K+ and SO42
      2. NH4+ and S2−
      3. NH4+ and PO43
    Answer
    1. K2SO4, potassium sulfate
    2. (NH4)2S, ammonium sulfide
    3. (NH4)3PO4, ammonium phosphate

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Ca2+ and NO3
      2. Ca2+ and NO2
      3. W3+ and C2H3O2
    Answer
    1. Ca(NO3)2, calcium nitrate
    2. Ca(NO2)2, calcium nitrite
    3. W(C2H3O2)3, tungsten(III) acetate

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Pb4+ and SO42
      2. Na+ and NO3
      3. Li+ and CO32
    Answer
    1. Pb(SO4)2, lead(IV) sulfate
    2. NaNO3, sodium nitrate
    3. Li2CO3, lithium carbonate

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. NH4+ and N3−
      2. Mg2+ and CN
      3. Al3+ and OH
    Answer
    1. (NH4)3N, ammonium nitride
    2. Mg(CN)2, magnesium cyanide
    3. Al(OH)3, aluminum hydroxide

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Ag+ and SO32
      2. Na+ and HCO3
      3. Fe3+ and ClO3
    Answer
    1. Ag2SO3, silver sulfite
    2. NaHCO3, sodium bicarbonate or sodium hydrogen carbonate
    3. Fe(ClO3)3, iron(III) chlorate

     

    1. Give the formula and name for each ionic compound formed between the two listed ions.
      1. Sn2+ and C2H3O2
      2. Au3+ and SO32
      3. Sr2+ and NO2
    Answer
    1. Sn(C2H3O2)2, tin(II) acetate
    2. Au2(SO3)3, gold(III) sulfite
    3. Sr(NO2)2, strontium nitrite

     

    1. The uranyl cation has the formula UO22+. Propose formulas and names for the ionic compounds between the uranyl cation and F, SO42, and PO43.
    Answer

    UO2F2, uranyl fluoride; UO2SO4, uranyl sulfate; (UO2)3(PO4)2, uranyl phosphate

     

    1. The permanganate anion has the formula MnO4. Propose formulas and names for the ionic compounds between the permanganate ion and K+, Ca2+, and Fe3+.
    Answer

    KMnO4, potassium permangante; Ca(MnO4)2, calcium permanganate; Fe(MnO4)3, iron(III) permanganate

     

    1. For each of the following pairs of ions, write the formula of the compound they will form:
      1. Ca2+, S2−
      2. \(\ce{NH4+}\), \(\ce{SO4^2-}\)
      3. Al3+, Br
      4. Na+, \(\ce{SO4^2-}\)
      5. Mg2+, \(\ce{PO4^3-}\)
    Answer
    1. CaS
    2. (NH4)2SO4
    3. AlBr3
    4. Na2SO4
    5. Mg3(PO4)2

     

    1. For each of the following pairs of ions, write the formula of the compound they will form:
      1. K+, O2−
      2. \(\ce{NH4+}\), \(\ce{PO4^3-}\)
      3. Al3+, O2−
      4. Li+, \(\ce{CO3^2-}\)
      5. Ba2+, \(\ce{PO4^3-}\)
    Answer
    1. K2O
    2. (NH4)3PO4
    3. Al2O3
    4. Li2CO3
    5. Ba3(PO4)2

     

    1. Write the formulas for each of the following compounds:
      1. potassium phosphate
      2. copper(II) sulfate
      3. calcium chloride
      4. titanium(IV) oxide
      5. ammonium nitrate
    Answer
    1. K3PO4
    2. CuSO4
    3. CaCl2
    4. TiO2
    5. NH4NO3

     

    1. Name each of the following compounds:
      1. Ca(ClO3)2
      2. FeSO4
      3. CaCO3
      4. AgNO2
      5. Ni(CN)3
    Answer
    1. calcium chlorate
    2. iron(II) sulfate
    3. calcium carbonate
    4. silver nitrite
    5. nickel(III) cyanide

     

    5.8: Binary Molecular Compounds

    1. What is the stem of fluorine used in molecule names? CF4 is one example.
    Answer

    fluor–

     

    1. What is the stem of bromine used in molecule names? SiBr4 is an example.
    Answer

    brom–

     

    1. Give the proper name for each molecule.
      1. PF3
      2. SCl2
      3. N2O3
    Answer
    1. phosphorus trifluoride
    2. sulfur dichloride
    3. dinitrogen trioxide

     

    1. Give the proper name for each molecule.
      1. NO
      2. CS2
      3. As2O3
    Answer
    1. nitrogen monoxide
    2. carbon disulfide
    3. diarsenic trioxide

     

    1. Give the proper name for each molecule.
      1. XeF2
      2. O2F2
      3. SF6
    Answer
    1. xenon difluoride
    2. dioxygen difluoride
    3. sulfur hexafluoride

     

    1. Give the proper name for each molecule.
      1. P4O10
      2. B2O3
      3. P2S3
    Answer
    1. tetraphosphorus decoxide
    2. diboron trioxide
    3. diphosphorus trisulfide

     

    1. Give the proper name for each molecule.
      1. N2O
      2. N2O4
      3. N2O5
    Answer
    1. dinitrogen monoxide
    2. dinitrogen tetroxide
    3. dinitrogen pentoxide

     

    1. Give the proper name for each molecule.
      1. SO2
      2. Cl2O
      3. XeF6
    Answer
    1. sulfur dioxide
    2. dichlorine monoxide
    3. xenon hexafluoride

     

    1. Give the proper formula for each name.
      1. dinitrogen pentoxide
      2. tetraboron tricarbide
      3. phosphorus pentachloride
    Answer
    1. N2O5
    2. B4C3
    3. PCl5

     

    1. Give the proper formula for each name.
      1. nitrogen triiodide
      2. diarsenic trisulfide
      3. iodine trichloride
    Answer
    1. NI3
    2. As2S3
    3. ICl3

     

    1. Give the proper formula for each name.
      1. dioxygen difluoride
      2. dinitrogen trisulfide
      3. xenon tetrafluoride
    Answer
    1. O2F2
    2. N2S3
    3. XeF4

     

    1. Give the proper formula for each name.
      1. chlorine dioxide
      2. sulfur dibromide
      3. dinitrogen trioxide
    Answer
    1. ClO2
    2. SBr2
    3. N2O3

     

    1. Give the proper formula for each name.
      1. iodine trifluoride
      2. xenon trioxide
      3. disulfur decafluoride
    Answer
    1. IF3
    2. XeO3
    3. S2F10

     

    1. Give the proper formula for each name.
      1. silicon dioxide
      2. carbon disulfide
      3. disulfur dibromide
    Answer
    1. SiO2
    2. CS2
    3. S2Br2

     

    5.9: Acids

    1. Give the formula for each acid.
      1. chloric acid
      2. hydroiodic acid
    Answer
    1. HClO3
    2. HI

     

    1. Give the formula for each acid.
      1. hydrosulfuric acid
      2. phosphorous acid
    Answer
    1. H2S
    2. H3PO3

     

    1. Name each acid.
      1. HF(aq)
      2. HNO3(aq)
      3. HC2H3O2(aq)
    Answer
    1. hydrofluoric acid
    2. nitric acid
    3. acetic acid

     

    1. Name each acid.
      1. H2SO4(aq)
      2. H3PO4(aq)
      3. HCl(aq)
    Answer
    1. sulfuric acid
    2. phosphoric acid
    3. hydrochloric acid

     

    5.10: Nomenclature Summary

    1. Name the following compounds:
      1. HClO2
      2. CuO
      3. K2SO4
      4. BrCl3
      5. HBr
      6. AlF3
    Answer
    1. chlorous acid
    2. copper(II) oxide
    3. potassium sulfate
    4. bromine trichloride
    5. hydrobromic acid
    6. aluminum fluoride

     

    1. Name the following compounds:
      1. NaF
      2. (NH4)2O
      3. MnCl3
      4. H2S
      5. P4O6
      6. HNO3
    Answer
    1. sodium fluoride
    2. ammonium oxide
    3. manganese(III) chloride
    4. hydrosulfuric acid
    5. tetraphosphorus hexoxide
    6. nitric acid

     

    1. Write the formulas of the following compounds:
      1. strontium bromide
      2. acetic acid
      3. lead(II) oxide
      4. gold(III) hydroxide
      5. hydrofluoric acid
      6. diphosphorus pentasulfide
      7. aluminum sulfite
      8. krypton tetrafluoride
    Answer
    1. SrBr2
    2. HC2H3O2
    3. PbO
    4. Au(OH)3
    5. HF
    6. P2S5
    7. Al2(SO3)3
    8. KrF4

     

    1. Write the formulas of the following compounds:
      1. lithium carbonate
      2. silver sulfide
      3. molybdenum(III) nitride
      4. diboron hexahydride
      5. sulfuric acid
      6. trisulfur heptachloride
      7. manganese(IV) chlorate
      8. hydrobromic acid
    Answer
    1. Li2CO3
    2. Ag2S
    3. MoN
    4. B2H6
    5. H2SO4
    6. S3Cl7
    7. Mn(ClO3)4
    8. HBr

     

    1. Write the formulas of the following compounds:
      1. chlorine dioxide
      2. carbonic acid
      3. potassium phosphide
      4. nickel(III) nitrite
      5. aluminum chlorite
      6. carbon disulfide
    Answer
    1. ClO2
    2. H2CO3
    3. K3P
    4. Ni(NO2)3
    5. Al(ClO2)3
    6. CS2

     

    1. Write the formulas of the following compounds:
      1. barium chloride
      2. xenon dioxide
      3. iron(III) nitrate
      4. acetic acid
      5. dinitrogen trioxide
      6. tin(IV) chloride
    Answer
    1. BaCl2
    2. XeO2
    3. Fe(NO3)3
    4. HC2H3O2
    5. N2O3
    6. SnCl4

     

    Contributions & Attributions


    5.E: Exercises is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Anonymous.