Chapter 3

Match the following. A) I(s) B) Cl(g) C) O(g) D) Cl2(g) E) Ne2(g) F) Ne(g) G) Ca(s) H) O2(g) I) I2(s) J) Ca2(s) 1) oxygen 2) chlorine 3) neon 4) calcium 5) iodine

1) H 2) D 3) F 4) G 5) I

Describe the difference between a molecular formula and an empirical formula. Give an example.

A molecular formula is the exact number of each type of atom necessary to build a specific molecule. An empirical formula is simply the smallest whole number ratio between atoms in a compound. For example, C2H4 is the molecular formula for ethene. The empirical formula for ethene is CH2, the smallest whole number ratio between the atoms.

How many moles of N2O3 contain 2.55 × 1024 oxygen atoms? A) 1.41 moles N2O3 B) 4.23 moles N2O3 C) 12.7 moles N2O3 D) 7.87 moles N2O3 E) 2.82 moles N2O3

A) 1.41 moles N2O3

Calculate the molar mass of C8H6O4. A) 166.13 g/mol B) 182.09 g/mol C) 150.18 g/mol D) 172.13 g/mol

A) 166.13 g/mo

Calculate the molar mass for Mg(ClO4)2. A) 223.21 g/mol B) 123.76 g/mol C) 119.52 g/mol D) 247.52 g/mol E) 75.76 g/mol

A) 223.21 g/mol

Calculate the mass percent composition of sulfur in Al2(SO4)3. A) 28.12% B) 9.372% C) 42.73% D) 21.38% E) 35.97%

A) 28.12%

How many C2H4 molecules are contained in 45.8 mg of C2H4? The molar mass of C2H4 is 28.05 g/mol. A) 9.83 × 10^20 C2H4 molecules B) 7.74 × 10^26 C2H4 molecules C) 2.71 × 10^20 C2H4 molecules D) 3.69 × 10^23 C2H4 molecules E) 4.69 × 10^23 C2H4 molecules

A) 9.83 × 10^20 C2H4 molecules

Determine the empirical formula for a compound that is 70.79% carbon, 8.91% hydrogen, 4.59% nitrogen, and 15.72% oxygen. A) C18H27NO3 B) C18H27NO2 C) C17H27NO3 D) C17H26NO3

A) C18H27NO3

What is the empirical formula for C4H10O2? A) C2H5O B) CHO C) C2H4O D) CHO2 E) CH2O

A) C2H5O

Determine the empirical formula for a compound that contains C, H and O. It contains 51.59% C and 35.30% O by mass. A) C2H6O B) CHO C) C4H13O2 D) CH4O3 E) CH3O

A) C2H6O

Write a possible molecular formula for C4H4O. A) C8H8O2 B) C12H12O2 C) C2H2O D) C8H8O

A) C8H8O2

Which of the following is one possible form of pentane? A) CH3CH2CH2CH2CH3 B) CH3CH=CHCH2CH3 C) CH3CH2CH2CH2CH2CH3 D) CH3CH2CH2CH2CH2NH2 E) CH3CH2-O-CH2CH2CH3

A) CH3CH2CH2CH2CH3

Give the formula for sulfurous acid. A) H2SO3 B) HSO3 C) H2SO4 D) HSO4

A) H2SO3

Identify the formula for nitric acid. A) HNO3 B) HNO2 C) HNO D) HNO4

A) HNO3

Which of the following is an ionic compound? A) LiCl B) NO2 C) PCl3 D) CF4 E) SeBr2

A) LiCl

What is the chemical formula for magnesium hydride? A) MgH2 B) MgOH C) MgOH2 D) Mg(OH)2

A) MgH2

Write the formula for strontium nitride. A) Sr3N2 B) Sr(NO3)2 C) SrN D) Sr2N3 E) Sr(NO2)2

A) Sr3N2

Which one of the following compounds contains ionic bonds? A) SrO B) HBr C) PBr3 D) SiO2

A) SrO

What type of bonding is found in the compound OF2? A) covalent bonding B) hydrogen bonding C) ionic bonding D) metallic bonding

A) covalent bonding

Determine the name for N2O5. A) dinitrogen pentoxide B) nitrogen oxide C) nitrogen (IV) oxide D) nitrogen (II) oxide E) nitrogen tetroxide

A) dinitrogen pentoxide

An aqueous solution of H2S is named A) hydrosulfuric acid. B) hydrosulfurous acid. C) sulfuric acid. D) sulfurous acid.

A) hydrosulfuric acid.

A covalent bond is best described as A) the sharing of electrons between atoms. B) the transfer of electrons. C) a bond between a metal and a nonmetal. D) a bond between a metal and a polyatomic ion. E) a bond between two polyatomic ions.

A) the sharing of electrons between atoms.

Determine the name for TiCO3. Remember that titanium forms several ions. A) titanium (II) carbonate B) titanium carbide C) titanium carbonite D) titanium (II) carbonite E) titanium (I) carbonate

A) titanium (II) carbonate

Describe the difference between ionic and molecular compounds. Give an example of each.

An ionic compound is formed between a metal and a nonmetal (or polyatomic ions) and is held together through the attraction of opposite charges. An example is NaCl. A molecular compound is usually formed between 2 or more nonmetals and is held together through the sharing of electrons between atoms. An example is CO2.

Balance the following equation. ____ C10H12 + ____ O2 → ____ H2O + ____ CO2

Answer: 1 C10H12 + 13 O2 → 6 H2O + 10 CO2

How can one compound contain both ionic and covalent bonds? Give an example.

Answer: An ionic compound that contains a polyatomic ion, such as NaNO3, has both ionic bonds (that hold the sodium and nitrate ions together) as well as covalent bonds (that hold the atoms within the nitrate ion together).

Can you predict the chemical formula for a covalent compound between nitrogen and oxygen?

Answer: No, since nitrogen and oxygen are both nonmetals, they combine by sharing electrons. This can be done in multiple different ways. Some possible compounds are N2O, N2O3, NO2.

Why aren't prefixes used in naming ionic compounds?

Answer: The charges on the ions dictate how many must be present to form a neutral unit. Molecular compounds do not have such constraints and therefore must use prefixes to denote the number of atoms present.

List the elements in a hydrocarbon.

Answer: hydrogen and carbon

Give the name for HNO2.

Answer: nitrous acid

Describe the difference between an atomic element and a molecular element.

Atomic elements exist in nature with a single atom at their basic unit; molecular elements exist in nature with more than one atom as their basic unit.

How many moles are there in 3.00 g of ethanol, CH3CH2OH? A) 0.00725 mol B) 0.0652 mol C) 15.3 mol D) 138 mol

B) 0.0652 mol

Calculate the mass percent composition of lithium in Li3PO4. A) 26.75% B) 17.98% C) 30.72% D) 55.27% E) 20.82%

B) 17.98%

How many moles of PCl3 contain 3.68 × 1025 chlorine atoms? A) 61.1 moles PCl3 B) 20.4 moles PCl3 C) 16.4 moles PCl3 D) 54.5 moles PCl3 E) 49.1 moles PCl3

B) 20.4 moles PCl3

Calculate the molar mass of Al(C2H3O2)3. A) 86.03 g/mol B) 204.13 g/mol C) 56.00 g/mol D) 258.09 g/mol E) 139.99 g/mol

B) 204.13 g/mol

What is the molar mass of nitrogen gas? A) 14.0 g/mol B) 28.0 g/mol C) 6.02 × 1023 g/mol D) 1.20 × 1023 g/mol

B) 28.0 g/mol

What is the mass, in kg, of 6.89 × 1025 molecules of CO2? The molar mass of CO2 is 44.01 g/mol. A) 3.85 kg B) 5.04 kg C) 2.60 kg D) 3.03 kg E) 6.39 kg

B) 5.04 kg

What is the mass of a single fluorine molecule, F2? A) 3.155 × 10-23 g B) 6.310 × 10-23 g C) 19.00 g D) 38.00 g

B) 6.310 × 10-23 g

What is the mass of 0.500 mol of dichlorodifluoromethane, CCl2F2? A) 4.14 × 10-3 g B) 60.5 g C) 121 g D) 242 g

B) 60.5 g

Give the mass percent of carbon in C14H19NO2. A) 38.89% B) 72.07% C) 5.17% D) 2.78%

B) 72.07%

Which of the compounds C4H10, BaCl2, Ni(NO3)2, SF6 are expected to exist as molecular compounds? A) only C4H10 B) C4H10 and SF6 C) C4H10, Ni(NO3)2, and SF6 D) BaCl2 and Ni(NO3)2

B) C4H10 and SF6

Determine the molecular formula of a compound that has a molar mass of 183.2 g/mol and an empirical formula of C2H5O2. A) C2H5O2 B) C6H15O6 C) C3H7O3 D) C4H10O4 E) C8H20O8

B) C6H15O6

The chemical formula for nitrous acid is A) H3N(aq). B) H NO2(aq). C) H NO3(aq). D) H2N2O6(aq).

B) H NO2(aq).

Write a balanced equation to show the reaction of sulfurous acid with lithium hydroxide to form water and lithium sulfite. A) H2SO4(aq) + LiOH(aq) → H2O(l) + Li2SO4(aq) B) H2SO3(aq) + 2 LiOH(aq) → 2 H2O(l) + Li2SO3(aq) C) HSO3(aq) + LiOH(aq) → H2O(l) + LiSO3(aq) D) HSO4(aq) + LiOH(aq) → H2O(l) + LiSO4(aq) E) H2S(aq) + 2 LiOH(aq) → 2 H2O(l) + Li2S(aq)

B) H2SO3(aq) + 2 LiOH(aq) → 2 H2O(l) + Li2SO3(aq)

What is the empirical formula for Hg2(NO3)2? A) Hg2(NO3)2 B) HgNO3 C) Hg(NO3)2 D) Hg2NO3 E) Hg4(NO3)4

B) HgNO3

Which of the following is an ionic compound? A) SCl2 B) Mg3(PO4)2 C) Cl2O D) CH2O E) PF5

B) Mg3(PO4)2

The solid compound, Na4SiO4, contains A) Na+, Si4+, and O2- ions. B) Na+ and SiO44- ions. C) Na4+ and SiO44- ions. D) Na4SiO4 molecules.

B) Na+ and SiO44- ions.

In which set do all elements tend to form cations in binary ionic compounds? A) K, Ga, O B) Sr, Ni, Hg C) N, P, Bi D) O, Br, I

B) Sr, Ni, Hg

Determine the name for Cl2O. A) chlorine oxide B) dichlorine monoxide C) chlorine (I) oxide D) chlorine (II) oxide E) chlorate

B) dichlorine monoxide

The ion, IO2-, is named A) iodate ion. B) iodite ion. C) iodine dioxide ion. D) iodine(II) oxide ion.

B) iodite ion.

Which of the compounds, Li3N, NH3, C3H8, IF3 are ionic compounds? A) only C3H8 B) only Li3N C) Li3N and NH3 D) N H3, C3H8, and IF3

B) only Li3N

Rb2S is named A) rubidium disulfide. B) rubidium sulfide. C) rubidium(II) sulfide. D) rubidium sulfur.

B) rubidium sulfide.

Give the name for NaNO3. A) sodium nitrite B) sodium nitrate C) sodium pernitrate D) sodium hyponitrite E) sodium hyponitrate

B) sodium nitrate

An ionic bond is best described as A) the sharing of electrons. B) the transfer of electrons from one atom to another. C) the attraction that holds the atoms together in a polyatomic ion. D) the attraction between 2 nonmetal atoms. E) the attraction between 2 metal atoms.

B) the transfer of electrons from one atom to another.

Give the name for SnO. A) tin (I) oxide B) tin (II) oxide C) tin (III) oxide D) tin (IV) oxide

B) tin (II) oxide

Write the name for Sn(SO4)2. Remember that Sn forms several ions. A) tin (I) sulfite B) tin (IV) sulfate C) tin sulfide D) tin (II) sulfite E) tin (I) sulfate

B) tin (IV) sulfate

How many moles of C3H8 contain 4.95 × 1024 hydrogen atoms? A) 8.22 moles C3H8 B) 6.58 moles C3H8 C) 1.03 moles C3H8 D) 9.73 moles C3H8 E) 3.09 moles C3H8

C) 1.03 moles C3H8

Write a balanced equation to show the reaction of gaseous ethane with gaseous oxygen to form carbon monoxide gas and water vapor. A) 2 C2H6(g) + 7 O2(g) → 4 CO2(g) + 6 H2O(g) B) C2H6(g) + 5 O(g) → 2 CO(g) + 3 H2O(g) C) 2 C2H6(g) + 5 O2(g) → 4 CO(g) + 6 H2O(g) D) C2H6(g) + 7 O(g) → 2 CO2(g) + 3 H2O(g) E) 2 CH3(g) + 5 O(g) → 2 CO(g) + 3 H2O(g)

C) 2 C2H6(g) + 5 O2(g) → 4 CO(g) + 6 H2O(g)

Calculate the molar mass of Ca3(PO4)2. A) 87.05 g/mol B) 215.21 g/mol C) 310.18 g/mol D) 279.21 g/mol E) 246.18 g/mol

C) 310.18 g/mol

What is the mass of 9.44 × 1024 molecules of NO2? The molar mass of NO2 is 46.01 g/mol. A) 205 g B) 294 g C) 721 g D) 341 g E) 685 g

C) 721 g

Two samples of potassium iodide are decomposed into their constituent elements. The first sample produced 13.0 g of potassium and 42.3 g of iodine. If the second sample produced 24.4 kg of potassium, how many kg of iodine were produced? A) 13.3 kg B) 22.5 kg C) 79.4 kg D) 44.4 kg E) 92.4 kg

C) 79.4 kg

Combustion analysis of 63.8 mg of a C, H and O containing compound produced 145.0 mg of CO2 and 59.38 mg of H2O. What is the empirical formula for the compound? A) C5H2O B) CHO C) C3H6O D) C3H7O E) C6HO3

C) C3H6O

The chemical formula for calcium nitride is A) Ca(NO3)2. B) Ca(NO2)2. C) Ca3N2. D) CaN2.

C) Ca3N2.

Write the formula for the compound formed between potassium and sulfur. A) KS B) KS2 C) K2S D) K2SO3 E) K3S2

C) K2S

Which of the following elements has the least tendency to form an ion? A) Ca B) K C) Kr D) Se

C) Kr

Determine the molecular formula of a compound that has a molar mass of 92.0 g/mol and an empirical formula of NO2. A) N2O3 B) N3O6 C) N2O4 D) NO2 E) N2O5

C) N2O4

Give the formula for sodium chlorate. A) NaClO B) NaClO2 C) NaClO3 D) NaClO4

C) NaClO3

Which of the following is a molecular element? A) Kr B) Ag C) S D) Mg E) Ti

C) S

The chemical formula for the sulfite ion is A) S-. B) S 2-. C) SO32-. D) SO42-.

C) SO32-.

Write the name for Ca3(PO4)2. A) calcium (III) phosphite B) calcium (II) phosphite C) calcium phosphate D) tricalcium phosphorustetraoxide E) calcium phosphite

C) calcium phosphate

Determine the name for H2CO3. A) carbonous acid B) dihydrogen carbonate C) carbonic acid D) hydrocarbonic acid E) hydrocarbide acid

C) carbonic acid

The compound, ClO, is named A) chlorite. B) hypochlorite. C) chlorine monoxide. D) chlorine (II) oxide.

C) chlorine monoxide.

How many atoms of oxygen are contained in 47.6 g of Al2(CO3)3? The molar mass of Al2(CO3)3 is 233.99 g/mol. A) 1.23 × 1023 O atoms B) 2.96 × 1024 O atoms C) 2.87 × 1025 O atoms D) 1.10 × 1024 O atoms E) 3.19 × 1024 O atoms

D) 1.10 × 1024 O atoms

How many molecules are contained in 25.0 mL of butane? The density of butane is 0.6011 g/mL and the molar mass is 58.12 g/mol. A) 2.59 × 10^23 molecules butane B) 1.46 × 10^27 molecules butane C) 6.87 × 10^23 molecules butane D) 1.56 × 10^23 molecules butane E) 7.14 × 10^25 molecules butane

D) 1.56 × 10^23 molecules butane

How many millimoles of Ca(NO3)2 contain 4.78 × 10^22 formula units of Ca(NO3)2? The molar mass of Ca(NO3)2 is 164.10 g/mol. A) 12.6 mmol Ca(NO3)2 B) 13.0 mmol Ca(NO3)2 C) 20.7 mmol Ca(NO3)2 D) 79.4 mmol Ca(NO3)2 E) 57.0 mmol Ca(NO3)2

D) 79.4 mmol Ca(NO3)2

Write a balanced equation to show the reaction of aqueous aluminum acetate with aqueous ammonium phosphate to form solid aluminum phosphate and aqueous ammonium acetate. A) Al(C2H3O2)2(aq) + (NH4)2PO4(aq) → AlPO4(s) + 2 NH4C2H3O2(aq) B) Al(C2H3O2)2(aq) + (NH3)2PO4(aq) → AlPO4(s) + 2 NH3C2H3O2(aq) C) Al(CO3)2(aq) + (NH3)2PO4(aq) → AlPO4(s) + 2 NH3CO3(aq) D) Al(C2H3O2)3(aq) + (NH4)3PO4(aq) → AlPO4(s) + 3 NH4C2H3O2(aq) E) Al(CO2)3(aq) + (NH4)3PO3(aq) → AlPO3(s) + 3 NH4CO2(aq)

D) Al(C2H3O2)3(aq) + (NH4)3PO4(aq) → AlPO4(s) + 3 NH4C2H3O2(aq)

Give the correct formula for aluminum sulfate. A) Al22SO4 B) Al(SO4)3 C) Al3(SO4)2 D) Al2(SO4)3

D) Al2(SO4)3

Which of the following is the correct chemical formula for a molecule of astatine? A) At B) At- C) At+ D) At2

D) At2

Write the formula for barium nitrite. A) Ba3N2 B) BaNO3 C) BN D) Ba(NO2)2 E) B(NO2)3

D) Ba(NO2)2

Which of the following is a molecular compound? A) CuCl2 B) KCl C) NaNO3 D) CH3Cl E) RbBr

D) CH3Cl

What is the chemical formula for calcium hydroxide? A) CaH2 B) CaOH C) CaOH2 D) Ca(OH)2

D) Ca(OH)2

What is the chemical formula for iron(III) sulfate? A) Fe3S B) Fe3SO4 C) Fe2S3 D) Fe2(SO4)3

D) Fe2(SO4)3

Which of the following is a molecular element? A) Mg B) Ar C) Xe D) I E) Li

D) I

The chemical formula for lithium peroxide is A) LiOH. B) LiO2. C) Li2O. D) Li2O2.

D) Li2O2.

In which set do all elements tend to form anions in binary ionic compounds? A) C, S, Pb B) K, Fe, Br C) Li, Na, K D) N, O, I

D) N, O, I

Determine the empirical formula for a compound that is 36.86% N and 63.14% O by mass. A) NO B) N2O C) NO2 D) N2O3 E) NO3

D) N2O3

Determine the name for HClO3. A) hydrochloric acid B) hydrochlorus acid C) chlorate acid D) chloric acid E) perchloric acid

D) chloric acid

Determine the name for CoCl2∙6H2O. Remember that Co forms several ions. A) cobalt chloride hydrate B) cobalt (I) chloride heptahydrate C) cobalt (II) chloride heptahydrate D) cobalt (II) chloride hexahydrate E) cobalt (I) chloride

D) cobalt (II) chloride hexahydrate

The compound, Cu(N O2)2, is named A) copper nitrite(II). B) copper(I) nitrite. C) copper(I) nitrite(II). D) copper(II) nitrite.

D) copper(II) nitrite.

Identify the principal component of natural gas. A) propane B) ethane C) n-butane D) methane E) n-pentane

D) methane

Determine the volume of hexane that contains 5.33 × 1022 molecules of hexane. The density of hexane is 0.6548 g/mL and its molar mass is 86.17 g/mol. A) 8.59 mL B) 13.5 mL C) 7.40 mL D) 12.4 mL E) 11.6 mL

E) 11.6 mL

How many moles of C3H8 contain 9.25 × 1024 molecules of C3H8? A) 65.1 moles C3H8 B) 28.6 moles C3H8 C) 34.9 moles C3H8 D) 46.2 moles C3H8 E) 15.4 moles C3H8

E) 15.4 moles C3H8

How many N2O4 molecules are contained in 76.3 g N2O4? The molar mass of N2O4 is 92.02 g/mol. A) 5.54 × 10^25 N2O4 molecules B) 7.26 × 10^23 N2O4 molecules C) 1.38 × 10^24 N2O4 molecules D) 4.59 × 10^25 N2O4 molecules E) 4.99 × 10^23 N2O4 molecules

E) 4.99 × 10^23 N2O4 molecules

How many sodium ions are contained in 99.6 mg of Na2SO3? The molar mass of Na2SO3 is 126.05 g/mol. A) 1.52 × 10^27 sodium ions B) 4.76 × 10^20 sodium ions C) 2.10 × 10^21 sodium ions D) 1.05 × 10^21 sodium ions E) 9.52 × 10^20 sodium ions

E) 9.52 × 10^20 sodium ions

Write the formula for copper (II) sulfate pentahydrate. A) Cu2SO3∙H5 B) Cu2S∙H2O C) CuS∙5H2O D) (CuSO4)5 E) CuSO4∙5H2O

E) CuSO4∙5H2O

Which of the following is an atomic element? A) Br B) H C) N D) O E) Mg

E) Mg

Which of the following is a molecular compound? A) NaCN B) LiOH C) SrI2 D) ZnS E) P4O10

E) P4O10

Determine the empirical formula for a compound that is found to contain 10.15 mg P and 34.85 mg Cl. A) P3Cl B) PCl C) PCl2 D) P2Cl3 E) PCl3

E) PCl3

Determine the name for aqueous HBr. A) bromic acid B) bromous acid C) hydrobromous acid D) hydrogen bromate E) hydrobromic acid

E) hydrobromic acid

Determine the name for P4O10. A) phosphorus (IV) oxide B) diphosphorus pentoxide C) phosphorus oxide D) phosphorus (II) oxide E) tetraphosphorus decoxide

E) tetraphosphorus decoxide