Chemistry Final Ch 6,7,10

In writing the chemical equation for a precipitation reaction, what abbreviation of the physical state must appear with one of the products? A) (s) B) (g) C) (l) D) (w) E) none of the above

A) (s)

What are the coefficients for the following reaction when it is properly balanced? ___HCl + ___Mg → ___MgCl2 + ___H2 A) 2, 1, 1, 1 B) 2, 1, 2, 2 C) 1, 2, 1/2, 1 D) 1, 1, 1, 2 E) none of the above

A) 2, 1, 1, 1

Consider the Lewis structures for the compound SO3 and the polyatomic ions SO32- and SO42-. Which of these must exist as a set of resonance structures? A) SO3 only B) SO32- only C) SO42- only D) all of these show resonance E) none of these show resonance

A) SO3 only

The compound sodium sulfate is soluble in water. When this compound dissolves in water, which ion listed below would be present in solution? A) SO42- B) S2- C) O2- D) Na22+ E) none of the above

A) SO42-

What is the molecular geometry if you have a double bond, a single bond and 1 lone pair around the central atom? A) bent B) linear C) tetrahedral D) trigonal pyramidal E) not enough information

A) bent

What is the molecular geometry of SCl2? A) bent B) linear C) tetrahedral D) trigonal pyramidal E) not enough information

A) bent

23) Which of the following compounds is INSOLUBLE? A) magnesium phosphate B) magnesium sulfate C) magnesium iodide D) magnesium nitrate E) none of the above

A) magnesium phosphate

Which sequence below represents the proper order of increasing bond strength? A) single < double < triple B) double < single < triple C) single < triple < double D) triple < double < single E) none of the above

A) single < double < triple

The elements with the highest electronegativity values tend to be found in the: A) upper right-side of the periodic table. B) lower right-side of the periodic table. C) upper left-side of the periodic table. D) lower left-side of the periodic table. E) center of the periodic table.

A) upper right-side of the periodic table.

What is the molecular formula of a compound given the molar mass of the compound is 30.04 gram and the empirical formula is NH? A) NH B) N2H2 C) N2H6 D) N4H4 E) none of the above

B N2H2

Methane gas (CH4), on complete combustion in air, produces: 1. CO2 2. H2 3. H2O A) 1 and 2 only B) 1 and 3 only C) 2 and 3 only D) All of 1 and 2 only E) None

B) 1 and 3 only

Which of the following compounds would have a linear molecular geometry? 1. N2 2. H2S 3. CO2 A) 1 and 2 only B) 1 and 3 only C) 2 and 3 only D) 1,2 and 3 E) neither 1, 2,or 3

B) 1 and 3 only

What is the angle between electron groups in the tetrahedral geometry? A) 90° B) 109.5° C) 120° D) 180° E) not enough information

B) 109.5°

30) If you had an aqueous mixture that contained Ag+, K+, and Pb2+ cations, how many different solids could precipitate if a chloride solution was added? A) 1 B) 2 C) 3 D) 4 E) no solids will precipitate

B) 2

How many moles of carbon are in 3.5 moles of calcium carbonate? A) 10.5 B) 3.5 C) 7 D) 100.09 E) none of the above

B) 3.5

What is the correct Lewis structure for Br2? A) Br-Br B) : - : C) = D) : Br ≡ Br : E) none of the above

B) : - :

Which compound listed below will dissolve in carbon tetrachloride, CCl4? A) NaCl B) CS2 C) NH3 D) all of the compounds E) none of the compounds

B) CS2

What would be the formula of the precipitate that forms when Pb(NO3)2 (aq) and K2SO4 (aq) are mixed? A) K(NO3)2 B) PbSO4 C) PbK2 D) H2O E) none of the above

B) PbSO4

What type of a reaction occurs when a sodium hydroxide solution is mixed with an acetic acid solution? A) precipitation B) acid-base neutralization C) oxidation-reduction D) gas evolution E) no reaction

B) acid-base neutralization

Which term matches the definition: A separation of charge within a bond? A) coulombic attraction B) dipole moment C) pure covalent D) nonpolar covalent E) electronegativity

B) dipole moment

37) What is the electron geometry if you have 3 electron groups around the center atom? A) linear B) trigonal planar C) tetrahedral D) trigonal bipyramidal E) not enough information

B) trigonal planar

The central atom in the chlorite anion, ClO2- is surrounded by: A) one bonding and three unshared pairs of electrons. B) two bonding and two unshared pairs of electrons. C) two bonding and one unshared pair of electrons. D) two double bonds and no unshared pairs of electrons. E) none of the above

B) two bonding and two unshared pairs of electrons.

When the equation __Ca3N2 + __H2O → __Ca(OH)2 + __NH3 is balanced, the coefficient of H2O is: A) 2 B) 3 C) 6 D) 12 E) none of the above

C) 6

Which of the following statements about redox reactions is FALSE? A) Oxidation is the loss of electrons. B) Reduction is the gain of electrons. C) A reaction can result in either oxidation or reduction, not both. D) A reaction involving elemental oxygen is a redox reaction. E) All of the above statement are true.

C) A reaction can result in either oxidation or reduction, not both.

The Lewis model predicts that the formula of a compound formed between bromine and aluminum is: A) AlBr B) Al2Br C) AlBr3 D) AlBr2 E) none of the above

C) AlBr3

Which molecule listed below has a nonpolar covalent bond? A) NaCl B) H2O C) H2 D) all of the compounds E) none of the compounds

C) H2

A reaction which forms a solid product is an example of a(n): A) oxidation-reduction reaction. B) combustion reaction. C) precipitation reaction. D) gas evolution reaction. E) none of the above

C) precipitation reaction.

The electron geometry and the molecular geometry of ammonia (NH3) are, respectively: A) trigonal planar, bent. B) tetrahedral, tetrahedral. C) tetrahedral, trigonal pyramidal. D) tetrahedral, bent. E) none of the above

C) tetrahedral, trigonal pyramidal.

Before a chemical equation can be written, one must know: A) the atomic mass of all the elements involved. B) the molar mass of all the compounds. C) the symbols and formulas of all reactants and products. D) the number of moles of all reactants and products. E) none of the above.

C) the symbols and formulas of all reactants and products.

Which symbol should be used between two structures that represent resonance structures? A) → B) ← C) ↔ D) ≡ E) none of the above

C) ↔

What is the angle between electron groups in the linear electron geometry? A) 90° B) 109.5° C) 120° D) 180° E) not enough information

D) 180°

What are the coefficients for the following reaction when it is properly balanced? ___O2 + ___CH4 → ___CO2 + ___H2O A) 2, 1, 3, 1 B) 2, 3, 2, 2 C) 1, 3, 2, 1 D) 2, 1, 1, 2 E) none of the above

D) 2, 1, 1, 2

How many valence electrons are in the nitrate ion? A) 18 B) 22 C) 23 D) 24 E) 26

D) 24

Sodium metal reacts with water to form aqueous sodium hydroxide and hydrogen gas. Which equation below best describes the balanced equation for this reaction? A) Na + H2O → NaOH (aq) + H (g) B) S + H2O → SOH (aq) + H (g) C) Na + H2O → NaOH (aq) + H2 (g) D) 2Na + 2H2O → 2NaOH (aq) + H2 (g) E) 2Na + H2O → Na2OH (aq) + H (g)

D) 2Na + 2H2O → 2NaOH (aq) + H2 (g)

The total number of electrons to be counted for the Lewis structure of the PO43- polyatomic ion is: A) 8. B) 26. C) 29. D) 32. E) none of the above

D) 32.

How many bonding electrons are in the Lewis structure of carbon monoxide, CO? A) 2 B) 3 C) 4 D) 6 E) none of the above

D) 6

When the equation, ___O2 + ___C5H12 → ___CO2 + ___H2O is balanced, the coefficient: of O2 is: A) 3 B) 4 C) 5 D) 8 E) none of the above

D) 8

What is the correct Lewis structure for N2? A) N-N B) :-: C) = D) : N ≡ N : E) none of the above

D) : N ≡ N :

A compound has a molar mass of 180.18 g/mol. Given the following percent composition, calculate the molecular formula: 39.99% C, 6.73% H, 53.28% O. A) CH3O2 B) CH2O C) C3H6O3 D) C6H12O6 E) none of the above

D) C6H12O6

Which Lewis structure below correctly represents the compound formed between magnesium and sulfur? A) Mg⁺ [::]⁻ B) Mg⁺ [::]⁻2 Mg⁺ C) [::]⁻ Mg⁺2 [::]⁻ D) Mg⁺2 [::]⁻2 E) none of the above

D) Mg⁺2 [::]⁻2

When solid NaCl is stirred into water, which of the following is NOT true? A) Individual sodium and chloride ions are present. B) The solution will conduct electricity. C) The solution will taste salty. D) The NaCl will fail to dissociate. E) none of the above

D) The NaCl will fail to dissociate.

When a nonmetal bonds with a nonmetal: A) a molecular compound forms. B) a covalent bond is involved. C) electrons are shared. D) all of the above are true E) none of the above

D) all of the above are true

Which of the following compounds is SOLUBLE? A) aluminum hydroxide B) aluminum sulfide C) aluminum carbonate D) aluminum sulfate E) none of the above

D) aluminum sulfate

An aqueous solution is: A) any liquid with another compound dissolved in it. B) an ionic compound with water dissolved in it. C) water with a molecular compound dissolved in it. D) water with another compound dissolved in it. E) none of the above

D) water with another compound dissolved in it.

Which of the following is NOT evidence that a chemical reaction has occurred? A) color change when chemicals are contacted with each other B) solid formation when chemicals are contacted with each other C) gas formation when chemicals are contacted with each other D) emission of light when chemicals are contact with each other E) All of the above are evidence of a chemical reaction.

E) All of the above are evidence of a chemical reaction.

Which of the following statements about Lewis structures is FALSE? A) An octet is when an atom has 8 valence electrons. B) A duet is a stable electron configuration for helium. C) An ionic bond occurs when electrons are transferred. D) A covalent bond occurs when electrons are shared. E) All of the above statements are true.

E) All of the above statements are true.

All of the following compounds are soluble in water EXCEPT: A) NaCl. B) CaCl2. C) FeCl3. D) NH4Cl. E) PbCl2.

E) PbCl2.

Which of the following is NOT an acid? A) HClO4 B) HNO3 C) HC2H3O2 D) H2SO4 E) none of the above

E) none of the above

Determine the empirical formula of a compound containing 60.3% magnesium and 39.7% oxygen. A) MgO B) MgO2 C) Mg2O3 D) Mg2O E) none of the above

a MgO

What is the mass percent of carbon in oxalic acid, H2C2O4? A) 2.24 B) 13.3 C) 26.7 D) 34.5 E) none of the above

c 26.7

A 15.5 gram sample of diphosphorous pentoxide contains how many grams of phosphorous? A) 3.38 B) 1.69 C) 6.76 D) 13.5 E) none of the above

c 6.76

What is the mass percent of chlorine in hydrochloric acid? A) 2.8 B) 35.5 C) 97.2 D) 70.1 E) none of the above

c 97.2

61) A compound composed of only carbon and hydrogen is 25.2% hydrogen by mass. The empirical formula for this compound is: A) CH 0.25 B) C3H C) CH4 D) C2H8 E) none of the above

c CH4

One mole of (NH4)2HPO4 contains how many moles of hydrogen atoms? A) 4 B) 2 C) 8 D) 9 E) none of the above

d 9

A chromium oxide compound contains 104.0 grams of chromium and 48.0 grams of oxygen. What is the most likely empirical formula of this compound? A) CrO B) CrO2 C) CrO3 D) Cr2O3 E) Cr3O2

d Cr2O3

1) A reaction which forms a gaseous product is an example of a(n)________. A) oxidation-reduction reaction B) combustion reaction C) precipitation reaction D) gas evolution reaction E) none of the above

d gas evolution

A chemical bond is classified as a covalent bond if it involves the transfer of electrons.

false

A precipitation reaction will occur when sodium chloride is mixed with potassium nitrate.v

false

Bubbles in water that appear during boiling show that a chemical reaction is occurring.

false

Li : is the proper Lewis structure (dot structure) for lithium.

false

The Lewis structure for O2 contains a triple bond.

false

The Lewis theory predicts that the formula for a compound of magnesium and sulfur is MgS2.

false

The correct formula for calculating mass percent of X in compound XY is: MASS OF X/MASS OF Y = Mass % X

false

The electron geometry of a molecule is never the same as its molecular geometry.

false

The following reaction IS balanced: AgNO3 + 2NH4Cl → AgCl + (NH4)2NO3

false

The formation of a gas is evidence of a chemical reaction while the emission of light is not.

false

The reaction of baking soda and vinegar to produce carbon dioxide gas is an example of a precipitation reaction.

false

The sulfate ion contains 28 valence electrons.

false

When calculating the number of electrons for the Lewis structure of a polyatomic ion, subtract one electron for each negative charge.

false

C2H3O2 could be an empirical formula.

true

Color change is evidence that a chemical reaction has occurred.

true

Combustion reactions are a subcategory of oxidation-reduction reactions.

true

Lewis structures only use the valence electrons in determining the bonding.

true

Li+, Na+, K+ and NH4+ compounds are soluble.

true

One mole of lead(II) nitrate contains six moles of oxygen atoms.

true

The Lewis structure of water has two sets of lone pair electrons.

true

The double bond is shorter and stronger than a single bond.

true

The molar mass of a compound in grams per mole is numerically equal to the formula mass of the compound in atomic mass units.

true

The molar mass of a compound serves as a conversion factor between grams and moles. true

true

The molecular formula is equal to the empirical formula multiplied by a whole number integer

true

When balancing a chemical equation you may alter the coefficients but not the subscripts in the equation.

true