Ch 5 Molecules & Compounds STUDY SHEET Accelerated Chemistry /100 Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) When elements combine to form compounds, 1) A) their properties do not change. B) their properties change completely. C) their properties are completely random. D) their properties are an average of all elements in the compound. 2) The first chemist to formally state the law of constant composition was. 2) A) Dalton B) Rutherford C) Mendeleev D) Proust 3) The law of constant composition states: 3) A) All samples of a given compound have the same proportions of their constituent elements. B) The nucleus is a dense region of positive charge that always contains protons and neutrons. C) All atoms of a given element have a constant composition and are different than atoms of any other element. D) Matter cannot be either created or destroyed in a chemical reaction. 4) The oxygen-to-hydrogen mass ratio of water is always 8.0 is an example of what fundamental law? A) Law of Constant Whole Number Ratio B) Law of Constant Composition C) Law of Conservation of Mass D) Law of Constant Mass Ratio 4) 5) What is the oxygen-to-hydrogen mass ratio for H 2 O 2? 5) A) 0.125 B) 4 C) 8 D) 16 6) The phosphorous-to-hydrogen mass ratio is 10.2 for a compound. This ratio could correspond to the compound A) PH6. B) PH3. C) PH2. D) PH. 6) 7) What is the oxygen-to-sulfur mass ratio of sulfur dioxide? 7) A) 0.5 B) 1.0 C) 2.0 D) 16 8) Which of the following statements about chemical formulas is FALSE? 8) A) The subscripts represent the relative mass of each type of atom in the compound. B) Different compounds made of the same elements have different subscripts. C) The subscripts do not change for a given compound. D) The subscripts represent the relative number of each type of atom in the compound. 9) How many total atoms are in the formula Al 2 (CO 3 ) 3? 9) A) 9 B) 14 C) 8 D) 12 1
10) How many carbon atoms are in the formula Al 2 (CO 3 ) 3? 10) A) 3 B) 9 C) 6 D) 1 11) How many oxygen atoms are in the formula Al 2 (CO 3 ) 3? 11) A) 6 B) 9 C) 3 D) 1 12) Which formula shows the proper use of parentheses? 12) A) Ca(SO4) B) (NH4)3(PO4) C) Ca(NO3)2 D) Ca(F)2 13) How many of each type of atoms are there in the formula NH 4 C 2 H 3 O 2? 13) A) N = 1, H = 4, C = 2, O = 2 B) N = 1, H = 3, C = 2, O = 2 C) N = 4, H = 7, C = 2, O = 2 D) N = 1, H = 7, C = 2, O = 2 14) How many of each type of atom are there in the formula Ca 3 (PO 4 ) 2? 14) A) Ca = 3, P = 2, O = 4 B) Ca = 3, P = 2, O = 8 C) Ca = 3, P = 1, O = 4 D) Ca = 3, P = 1, O = 8 15) How many of each type of atom are there in the formula (NH4)2HPO4? 15) A) N = 2, H = 9, P = 1, O = 4 B) N = 1, H = 5, P = 1, O = 4 C) N = 2, H = 8, P = 1, O = 4 D) N = 2, H = 5, P = 1, O = 4 16) What is the correct formula for a compound that has three oxygen atoms and one sulfur atom? 16) A) 3OS B) SO3 C) SO3 D) O3S 17) What is the correct formula of a compound that has ten oxygen atoms and four phosphorus atoms? A) 10OP 4 B) O 10 P 4 C) 4PO 10 D) P 4 O 10 17) 18) Carbon is considered which of the following? 18) A) molecular element B) atomic element C) molecular compound D) ionic compound 19) Which among the following elements does NOT exist as a diatomic molecule in nature? 19) A) nitrogen B) hydrogen C) fluorine D) neon 20) Carbon monoxide is considered which of the following? 20) A) molecular compound B) atomic element C) molecular element D) ionic compound 21) Fluorine is considered which of the following? 21) A) molecular element B) molecular compound C) atomic element D) ionic compound 22) Ammonium fluoride is considered which of the following? 22) A) molecular element B) molecular compound C) ionic compound D) atomic element 2
23) Which of the following species is a molecular element? 23) A) carbon dioxide B) neon C) chlorine D) sodium 24) Which of the following is a molecular compound? 24) A) potassium hydroxide B) nitrogen monoxide C) calcium acetate D) barium sulfide 25) What is the formula for an ionic compound made of barium and nitrogen? 25) A) Ba 2 N 3 B) BaN C) Ba 2 N 4 D) Ba 3 N 2 26) What is the formula for an ionic compound made of magnesium and sulfur? 26) A) MgS B) Mg 2 S C) Mg 2 S 3 D) MgS 2 27) What is the formula for an ionic compound made of carbon and oxygen? 27) A) CO B) CO 3 C) C 2 O D) CO 2 28) The ionic compound that forms between potassium and oxygen is 28) A) K2O. B) K2O2. C) KO. D) KO2. 29) What is the formula for an ionic compound made of aluminum and oxygen? 29) A) AlO B) Al 3 O 2 C) Al 2 O 3 D) AlO 2 30) What is the name of the ionic compound made of beryllium and chlorine? 30) A) beryllium chloride B) beryllium dichloride C) monoberyllium dichloride D) beryllium(ii) chloride 31) What is the name of the compound made from lithium and oxygen? 31) A) lithium(i) oxide B) lithium oxide C) lithium dioxide D) oxygen lithide 32) Which metal atom below would NOT be involved in formation of a Type II compound? 32) A) Mn B) Fe C) Ba D) Cr 33) What is the name of CoS? 33) A) cobalt monosulfide B) cobaltous sulfur C) cobalt(ii) sulfide D) cobalt sulfide 34) What is the name of Ca(NO3)2? 34) A) calcium nitride B) calcium nitrate C) calcium nitrite D) calcium dinitrite 35) Which formula shown is incorrect for the name given? 35) A) magnesium nitrite: Mg(NO 2 ) 3 B) potassium hydroxide: KOH C) aluminum sulfate: Al 2 (SO 4 )3 D) sodium hydrogen carbonate: NaHCO 3 3
36) Which formula shown is incorrect for the name given? 36) A) strontium carbonate: SrCO3 B) ammonium cyanide: NH4CN C) potassium acetate: KC2H3O2 D) lithium sulfate: LiSO4 37) What is the name of the compound whose formula is Na 2 O? 37) A) disodium oxide B) disodium monoxide C) sodium oxide D) sodium monoxide 38) What is the formula for the acetate polyatomic ion? 38) A) C 2 H 3 O- B) C 2 H 3 O 2 2- C) C 2 H 3 O 2 - D) C 3 H 2 O 3-39) What is the correct formula for potassium dichromate? 39) A) KCr2O7 B) K2Cr2O7 C) K2CrO4 D) K(CrO4)2 40) What is the correct formula for ammonium hydrogen sulfate? 40) A) (NH 4 ) 2 HSO 4 B) NH 4 HSO 4 C) Am 2 HSO 4 D) (NH 4 ) 2 SO 4 41) The formula for potassium chlorate is KClO 3. The formula for magnesium chloride is MgCl 2. What is the formula for magnesium chlorate? A) Mg 2 ClO 3 B) Mg(ClO 3 )2 C) MgClO 3 D) Mg 2 (ClO 3 ) 3 41) 42) The charge of a vanadium ion in the compound V2O5 is: 42) A) 10- B) 5+ C) 2+ D) 10+ 43) What is the correct formula for the hypochlorite polyatomic ion? 43) A) ClO 2 - B) ClO 3 - C) ClO- D) ClO 4-44) What is the correct name for the BrO4 1- ion? 44) A) perbromate B) bromate C) hypobromite D) bromite 45) Choose the pair of names and formulas that do NOT match. 45) A) copper(ii) nitride: Cu3N2 B) copper(i) nitrate: CuNO3 C) copper(ii) nitrite: Cu(NO2)2 D) all of these are correct 46) The name trisodium phosphate is incorrect for the compound Na3PO4 because 46) A) you cannot use a prefix for the first element of an ionic compound. B) this compound should be called trisodium monophosphate. C) you cannot use a prefix for the first element in a molecular compound. D) none of the above 47) What is the name of the molecular compound SF5? 47) A) sulfur pentafluoride B) sulfur heptafluoride C) sulfur hexafluoride D) none of the above 4
48) What is the name of the molecular compound SO 3? 48) A) sulfur(iv) oxide B) sulfur tetraoxide C) sulfur trioxide D) none of the above 49) What is correct name of the compound whose formula is N 2 O 4? 49) A) dinitrogen oxide B) nitrogen dioxide C) nitrogen tetroxide D) dinitrogen tetroxide 50) What is correct name of the compound whose formula is BF3? 50) A) boron(iii) fluoride B) boron fluoride C) boron trifluoride D) monoboron trifluorine 51) What would the formula of diiodine pentasulfide be? 51) A) I 2 S 5 B) I 2 S 7 C) I 4 S 9 D) I 5 S 2 52) What is the correct formula for the molecular compound heptaphosphorus octafluoride? 52) A) P 6 F 7 B) P 7 F 6 C) P 5 F 8 D) P 7 F 8 53) What is the proper name for HBr (aq)? 53) A) bromous acid B) hydrobromous acid C) hydrobromic acid D) hydrousbromic acid 54) What is the name of HI (aq)? 54) A) hydroiodous acid B) iodic acid C) iodous acid D) hydroiodic acid 55) What is the name of HIO 3 (aq)? 55) A) hydrogen iodate B) iodic acid C) hydroioidic acid D) iodous acid 56) What is the name of HNO 2 (aq)? 56) A) Nitric acid B) hydronitric acid C) Nitrous acid D) hydronitrous acid 57) A certain oxyacid is derived from the oxyanion SO3 2-. The formula for the oxyacid is 57) A) H2SO3. B) HSO3. C) H2SO4. D) H3SO3. 58) What is the formula mass of sulfurous acid? 58) A) 98.08 amu B) 66.08 amu C) 83.09 amu D) 82.08 amu 59) What is the formula mass for potassium nitrate? 59) A) 92.99 amu B) 85.11 amu C) 101.10 amu D) 117.11 amu 60) What is the formula mass for diboron tetrachloride? 60) A) 127.98 amu B) 234.34 amu C) 198.89 amu D) 163.43 amu 5
61) What is the formula mass of copper(ii) fluoride? 61) A) 90.00 B) 101.55 C) 165.10 D) 146.10 62) Which of the following has the largest formula mass? 62) A) NO 2 B) SiO 2 C) CO 2 D) SO 2 E) H 2 O 63) Which of the following compounds have the smallest formula mass? 63) A) CO 2 B) NO 2 C) SiO 2 D) SO 2 E) H 2 O 64) A compound has a formula mass of 61.98 amu and is comprised of atoms of sodium and oxygen in a definite ratio. The name of the compound described here is A) sodium monoxide. B) sodium dioxide. C) disodium oxide. D) sodium oxide. 64) 65) If the mass ratio of K to F in a compound is 2.06:1, how many grams of F are needed to react with 97.5 g of K? A) 0.0211 B) 2.11 C) 4.73 D) 47.3 65) 66) What is the mass ratio of Na to S in sodium sulfide? 66) A) 55.06 B) 1.43 C) 7.17 D) 0.717 67) How many O atoms are present in sodium chlorite? 67) A) 4 B) 1 C) 2 D) 6 68) How many C atoms are in ammonium acetate? 68) A) 3 B) 2 C) 1 D) 5 TRUE/FALSE. Write 'T' (A) if the statement is true and 'F' (B) if the statement is false. Correct the FALSE statements by changing the underlined word. 69) When elements combine to form compounds, their properties only change slightly. 69) 70) The properties of a compound are an average of the properties of the individual elements. 70) 71) Life could not exist with just 91 elements if they did not combine to form compounds. 71) 72) Although some substances we encounter in our routine lives are elements, most occur in the combined state. 72) 73) The law of constant composition states: All samples of a given compound have the same proportions of their constituent elements. 73) 74) The fact that water has an oxygen-to-hydrogen mass ratio of 8.0 illustrates the law of conservation of mass. 74) 75) The subscripts in a chemical formula represent the relative mass of each atom in a chemical compound. 75) 6
76) The subscripts in a chemical formula do not change for a given compound. 76) 77) Chemical formulas normally list the most metallic elements first. 77) 78) The formula of a compound comprised of two nitrogen atoms and one oxygen atom should be written properly as ON2. 78) 79) Molecular elements do not exist in nature. 79) 80) The element nitrogen normally exists in nature as a diatomic molecule. 80) 81) Carbon dioxide is an example of a molecular compound. 81) 82) The basic unit of an ionic compound is called the formula unit. 82) 83) SO2 is an ionic compound. 83) 84) Ionic compounds have a net charge of zero. 84) 85) Ionic compounds always contain positive and negative ions. 85) 86) In ionic compounds the net positive charge always equals the net negative charge. 86) 87) The ionic compound that forms between aluminum and oxygen is AlO. 87) 88) The ionic compound that forms between Mg and O is MgO. 88) 89) The correct formula for calcium fluoride is CaF 3. 89) 90) Ionic compounds are usually made up of a metal and a nonmetal. 90) 91) The ionic compound MgO is named manganese oxide. 91) 92) The name of KNO 3 is potassium nitratide. 92) 93) The correct formula for sodium permanganate is NaMgO4. 93) 94) Type II metal cations are usually found in the section of the periodic table known as the transition metals. 94) 95) If there are two ions in a series of oxoanions, the one with more oxygen is given the ending "-ite." 95) 96) The proper name for SF 6 is sulfur tetrafluoride. 96) 7
97) The proper name for the acid HF is hydrofluoric acid. 97) 98) The proper name for for HI is hydroiodic acid. 98) 99) The correct name for HNO 3 is hydronitric acid. 99) 100) The correct name for H 2 SO 3 is sulfurous acid. 100) 8