CP Final Review
Multiple Choice
Moles
____ 1. How many grams are there in 2.50 moles of chromium?
a. / 41.6 g / c. / 130.0 gb. / 20.8 g / d. / 60.0 g
_____2. The molar mass of aluminum sulfate is _____.
a. / 123 g/molb. / 214 g/mol
c. / 278 g/mol
d. / 342 g/mol
____ 3. Which one of the following compounds has the lowest molar mass?
a. / Carbon monoxide. / c. / Carbon dioxide.b. / Nitrogen dioxide. / d. / Nitrogen monoxide.
____ 4. How many oxygen atoms are there in 0.25 mole of oxygen gas?
a. / 3.011 x 1023 / c. / 1.556 x 1023b. / 6.022 x 1023 / d. / 1.204 x 1024
____ 5. A chemical formula includes the symbols of the elements in the compound and subscripts that indicate
a. / the number of moles in each element.b. / how many atoms or ions of each type are combined in the simplest unit.
c. / the formula mass.
d. / the charges on the elements or ions.
____ 6. How many atoms of fluorine are present in a molecule of carbon tetrafluoride, CF4?
a. / 1 / c. / 4b. / 2 / d. / 5
____ 7. Changing a subscript in a correctly written chemical formula
a. / changes the number of moles represented by the formula.b. / changes the charges on the other ions in the compound.
c. / changes the formula so that it no longer represents that compound.
d. / has no effect on the formula.
______8. How many grams are there in 1.5 moles of chlorine gas?
a. 35.5 g
b. 71.0 g
c. 106.5 g
d. 184.6 g
______9. The molar mass of MgI2 is _____.
a. / the sum of the masses of 1 mol of Mg and 2 mol of I.b. / the sum of the masses of 1 mol of Mg and 1 mol of I.
c. / the sum of the masses of 2 mol of Mg and 2 mol of I.
d. / impossible to calculate.
____ 10. The molar mass of NO2 is 46.01 g/mol. How many moles of NO2 are present in 114.95 g?
a. / 0.4003 mol / c. / 2.498 molb. / 1.000 mol / d. / 114.95 mol
____ 11. The molar mass of CCl4 is 153.81 g/mol. How many grams of CCl4 are needed to have 5.000 mol?
a. / 5 g / c. / 769.0 gb. / 30.76 g / d. / 796.05 g
____ 12. The molar mass of H2O is 18.015 g/mol. How many grams of H2O are present in 0.20 mol?
a. / 0.2 g / c. / 35.9 gb. / 3.6 g / d. / 89.9 g
______13. The empirical formula is always the accepted formula for a(n)
a. / atom. / c. / molecular compound.b. / molecule. / d. / ionic compound.
____ 14. The empirical formula for a compound shows the symbols of the elements with subscripts indicating the
a. / actual numbers of atoms in a molecule.b. / number of moles of the compound in 100 g.
c. / smallest whole-number ratio of the atoms.
d. / atomic masses of each element.
____ 15. The molecular formula for vitamin C is C6H8O6. What is the empirical formula?
a. / CHO / c. / C3H4O3b. / CH2O / d. / C2H4O2
____ 16. A compound's empirical formula is C2H5. If the formula mass is 58 amu, what is the molecular formula?
a. / C3H6 / c. / C5H8b. / C4H10 / d. / C5H15
____ 17. A compound's empirical formula is NO2. If the formula mass is 92 amu, what is the molecular formula?
a. / NO / c. / NO4b. / N2O2 / d. / N2O4
____ 18. The number of atoms in 1 mol of carbon is
a. / 6.022 x 1022. / c. / 5.022 x 1022.b. / 6.022 x 1023. / d. / 5.022 x 1023.
____ 19. Molar mass
a. / is the mass in grams of one mole of a substance.b. / is numerically equal to the average atomic mass of the element.
c. / both a and b
d. / neither a nor b
____ 20. A mass of 6.005 g of carbon (atomic mass 12.010 amu) contains
a. / 1 mol C. / c. / 0.5000 mol C.b. / 2 atoms C. / d. / 1 atom O.
____ 21. What is the number of moles of chemical units represented by 9.03 x 1024 units?
a. / 1.50 mol / c. / 10.0 molb. / 9.03 mol / d. / 15.0 mol
____ 22. A prospector finds 39.39 g of gold (atomic mass 196.9665 amu). She has
a. / 1.20 x1023 atoms. / c. / 4.30 x 1023 atoms.b. / 2.30 x 1023 atoms. / d. / 6.02 x 1023 atoms.
____ 23. A sample of tin (atomic mass 118.69 amu) contains 3.01 x 1023 atoms. The mass of the sample is
a. / 3.01 g. / c. / 72.6 g.b. / 59.3 g. / d. / 11 g.
____ 24. What is the percentage composition of CF4?
a. / 20% C, 80% F / c. / 16.8% C, 83.2% Fb. / 13.6% C, 86.4% F / d. / 81% C, 19% F
____ 25. What is the percentage composition of CuCl2?
a. / 33% Cu, 66% Cl / c. / 65.50% Cu, 34.50% Clb. / 50% Cu, 50% Cl / d. / 47.263% Cu, 52.737% Cl
d. / always equal to the total mass of the products.
Equations
____ 26. The law of conservation of mass follows from the concept that
a. / atoms are indivisible in chemical reactions.b. / atoms of different elements have different properties.
c. / matter is composed of atoms.
d. / atoms can be destroyed in chemical reactions.
____ 27. According to the law of conservation of mass, when sodium, hydrogen, and oxygen react to form a compound, the mass of the compound is ____ the sum of the masses of the individual elements.
a. / equal to / c. / less thanb. / greater than / d. / either greater than or less than
____ 28. Knowledge about what products are produced in a chemical reaction is obtained by
a. / inspecting the chemical equation. / c. / laboratory analysis.b. / balancing the chemical equation. / d. / writing a word equation.
____ 29. A chemical reaction has NOT occurred if the products have
a. / the same mass as the reactants.b. / less total bond energy than the reactants.
c. / more total bond energy than the reactants.
d. / the same chemical properties as the reactants.
____ 30. Which observation does NOT indicate that a chemical reaction has occurred?
a. / formation of a precipitate / c. / evolution of heat and lightb. / production of a gas / d. / change in total mass of substances
____ 31. A solid produced by a chemical reaction in solution that separates from the solution is called
a. / a precipitate. / c. / a molecule.b. / a reactant. / d. / the mass of the product.
____ 32. After the correct formula for a reactant in an equation has been written, the
a. / subscripts are adjusted to balance the equation.b. / formula should not be changed.
c. / same formula must appear as the product.
d. / symbols in the formula must not appear on the product side of the equation.
____ 33. In writing an equation that produces hydrogen gas, the correct representation of hydrogen gas is
a. / H. / c. / H2.b. / 2H. / d. / OH.
____ 34. To balance a chemical equation, it may be necessary to adjust the
a. / coefficients. / c. / formulas of the products.b. / subscripts. / d. / number of products.
____ 35. According to the law of conservation of mass, the total mass of the reacting substances is
a. / always more than the total mass of the products.b. / always less than the total mass of the products.
c. / sometimes more and sometimes less than the total mass of the products.
d. / always equal to the total mass of the products.
____ 36. A chemical equation is balanced when the
a. / coefficients of the reactants equal the coefficients of the products.b. / same number of each kind of atom appears in the reactants and in the products.
c. / products and reactants are the same chemicals.
d. / subscripts of the reactants equal the subscripts of the products.
____ 37. Which word equation represents the reaction that produces water from hydrogen and oxygen?
a. / Water is produced from hydrogen and oxygen.b. / Hydrogen plus oxygen yields water.
c. / H2 + O2 →water.
d. / Water can be separated into hydrogen and oxygen.
____38. For the formula equation 2Mg + O2 → 2MgO, the word equation would begin
a. / Manganese plus oxygen . . . / c. / Magnesium plus oxygen . . .b. / Molybdenum plus oxygen . . . / d. / Heat plus oxygen . . .
____39 . In an equation, the symbol for a substance in water solution is followed by
a. / (1). / c. / (aq).b. / (g). / d. / (s).
____ 40. The reaction 2Mg(s) + O2(g) → 2MgO(s) is a
a. / synthesis reaction. / c. / single-replacement reaction.b. / decomposition reaction. / d. / double-replacement reaction.
____ 41. The reaction Mg(s) + 2HCl(aq) → H2(g) + MgCl2(aq) is a
a. / composition reaction. / c. / single-replacement reaction.b. / decomposition reaction. / d. / double-replacement reaction.
____ 42. In the equation 2Al(s) + 3Fe(NO3)2(aq) → 3Fe(s) + 2Al(NO3)3(aq), iron has been replaced by
a. / nitrate. / c. / aluminum.b. / water. / d. / nitrogen.
____ 43. An insoluble gas that forms in a double-replacement reaction in aqueous solution
a. / bubbles out of solution. / c. / disassociates into ions.b. / forms a precipitate. / d. / reacts with the water.
____ 44. The formulas for the products of the reaction between sodium hydroxide and sulfuric acid are ____.
a. / Na2SO4 and H2O. / c. / SI4 and Na2O.b. / NaSO4 and H2O. / d. / S + O2 and Na.
____ 45. An element in the activity series can replace any element _____.
a. / in the periodic table. / c. / above it on the list.b. / below it on the list. / d. / in its group.
____ 46. What can be predicted by using an activity series?
a. / whether a certain chemical reaction will occurb. / the amount of energy released by a chemical reaction
c. / the electronegativity values of elements
d. / the melting points of elements
____ 47. According to the law of conservation of mass, when sodium, hydrogen, and oxygen react to form a compound, the mass of the compound is ____ the sum of the masses of the individual elements.
a. / equal to / c. / less thanb. / greater than / d. / either greater than or less than
____ 48. A chemical equation is balanced when the
a. / coefficients of the reactants equal the coefficients of the products.b. / same number of each kind of atom appears in the reactants and in the products.
c. / products and reactants are the same chemicals.
d. / subscripts of the reactants equal the subscripts of the products.
____ 49. Which word equation represents the reaction that produces water from hydrogen and oxygen?
a. / Water is produced from hydrogen and oxygen.b. / Hydrogen plus oxygen yields water.
c. / H2 + O2 → water.
d. / Water can be separated into hydrogen and oxygen.
____50. For the formula equation 2Mg + O2 → 2MgO, the word equation would begin
a. / Manganese plus oxygen . . . / c. / Magnesium plus oxygen . . .b. / Molybdenum plus oxygen . . . / d. / Heat plus oxygen . . .
____ 51 . In an equation, the symbol for a substance in water solution is followed by
a. / (1). / c. / (aq).b. / (g). / d. / (s).
____ 52 . When the equation Fe3O4 + Al → Al2O3 + Fe is correctly balanced, what is the coefficient of Fe?
a. / 3 / c. / 6b. / 4 / d. / 9
____53. Which coefficients correctly balance the formula equation NH4NO2(s) → N2(g) + H2O(l)?
a. / 1, 2, 2 / c. / 2, 1, 1b. / 1, 1, 2 / d. / 2, 2, 2
____54. Which coefficients correctly balance the formula equation CaO + H2O → Ca(OH)2?
a. / 2, 1, 2 / c. / 1, 2, 1b. / 1, 2, 3 / d. / 1, 1, 1
____ 55. The complete balanced equation for the reaction between zinc hydroxide and acetic acid is
a. / ZnOH + CH3COOH → ZnCH3COO + H2O.b. / Zn(OH)2 + CH3COOH → Zn + 2CO2 +3H2O.
c. / Zn(OH)2 + 2CH3COOH → Zn(CH3COO)2 + 2H2O.
d. / Zn(OH)2 + 2CH3COOH → Zn(CH3COO)2 + H2 + O2.
____ 56. What is the balanced equation for the combustion of sulfur?
a. / S(s) + O2(g) → SO(g) / c. / 2S(s) + 3O2(g) → SO3(s)b. / S(s) + O2(g) → SO2(g) / d. / S(s) + 2O2(g) → SO42–(aq)
____57 . Which equation is NOT balanced?
a. / 2H2 + O2 → 2H2Ob. / 4H2 + 2O2 → 4H2O
c. / H2 + H2 + O2 → H2O + H2O
d. / 2H2 + O2 → H2O
____ 58. The equation AX → A + X is the general equation for a
a. / synthesis reaction. / c. / combustion reaction.b. / decomposition reaction. / d. / single-replacement reaction.
____ 59. The equation AX + BY → AY + BX is the general equation for a
a. / synthesis reaction. / c. / single-replacement reaction.b. / decomposition reaction. / d. / double-replacement reaction.
____ 60. The equation A + X → AX is the general equation for a(n)
a. / combustion reaction. / c. / synthesis reaction.b. / ionic reaction. / d. / double-replacement reaction.
____ 61. In what kind of reaction does a single compound produce two or more simpler substances?
a. / decomposition reaction / c. / single-replacement reactionb. / synthesis reaction / d. / ionic reaction
____ 62. The equation A + BX → AX + B is the general equation for a
a. / double-replacement reaction. / c. / single-replacement reaction.b. / decomposition reaction. / d. / combustion reaction.
____ 63. In what kind of reaction do the ions of two compounds exchange places in aqueous solution to form two new compounds?
a. / synthesis reaction / c. / decomposition reactionb. / double-replacement reaction / d. / combustion reaction
____ 64. The reaction 2Mg(s) + O2(g) → 2MgO(s) is a
a. / synthesis reaction. / c. / single-replacement reaction.b. / decomposition reaction. / d. / double-replacement reaction.
____ 65. The reaction Mg(s) + 2HCl(aq) → H2(g) + MgCl2(aq) is a
a. / composition reaction. / c. / single-replacement reaction.b. / decomposition reaction. / d. / double-replacement reaction.
____ 66. The formulas for the products of the reaction between sodium hydroxide and sulfuric acid are
a. / Na2SO4 and H2O. / c. / SI4 and Na2O.b. / NaSO4 and H2O. / d. / S + O2 and Na.
Bonding and Molecular Geometry
____ 67. A mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together is called a(n)