Question 1

Cu + 2AgNO₃--> 2Ag + Cu(NO₃)₂In the reaction above, which element is oxidized? A)Cu B)Ag C)N D)O E)Oxidation does not occur in this reaction

Accepted Answer

Oxidation occurs when an element loses electrons over the course of a reaction. In this case, copper loses electrons and therefore undergoes oxidation.

Question 2

____CH₃OH(l) + _____O₂(g) --> _____CO₂(g) + _____H₂O(g)What set of coefficients correctly balances this equation? A)2, 3, 2, 1 B)1, 2, 2, 1 C)2, 3, 4, 2 D)2, 3, 3, 4 E)2, 3, 2, 4

Accepted Answer

Use the law of conservation of mass to balance this equation by inspection. The correct coefficients are 2, 3, 2, 4.

Question 3

2SO₂(g) + O₂(g) --> 2SO₃(g)What is the correct rate law for this reaction? A)r = k[SO₂][O₂] B)r = k[SO₃] C)r = k[SO₂]²[O₂] D)r = k[SO₃]² E)r = k[SO₃][SO₂][O₂]

Accepted Answer

When writing a rate law for a chemical reaction, use the concentrations of the reactants raised to the powers of their coefficients. The rate constant, k, is determined experimentally and cannot be determined with the information in this problem. Thus, the correct rate law is r = k[SO₂]²[O₂].

Question 4

80)0 grams of NaOH is dissolved in 3.0 moles of H?0. What is the mole fraction of NaOH in this solution?
A))20
B))37
C))40
D))64
E))79

Accepted Answer

The mole fraction for a compound indicates (moles of given compund) / (total moles of system). In this question, there are two moles of NaOH and five total moles in the system. Thus, the mole fraction is expressed as 2/5, or .40.

Question 5

NH₃(g) + CuO(s) --> N₂(g) + Cu(s) + H₂O(g)What set of coefficients correctly balances the above equation? A)3, 3, 1, 2, 3 B)3, 2, 1, 2, 2 C)2, 3, 1, 3, 3 D)1, 2, 3, 2, 2 E)3, 2, 1, 2, 3

Accepted Answer

The coefficients must balance the masses of the reactants and products. The correct set is 2, 3, 1, 3, 3.

Question 6

Which of the following elements displays bonding characterized by a delocalized "sea of electrons?"
A)Fluorine
B)Nitrogen
C)Copper
D)Sulfur
E)Argon

Accepted Answer

The delocalized "sea of electrons" model describes bonding in metals. Therefore, the only metal, copper, must display this type of bonding.

Question 7

Which of the following is the correct electron configuration for copper? A)[Ar] 4s²3d⁹ B)[Ar] 4s¹3d¹⁰ C)[Ar] 3s²3d⁹ D)[Ar] 3s¹3d¹⁰ E)[Kr] 4s²3d⁹

Accepted Answer

To write the abbreviated electron configuration for an element, begin with the noble gas in the period directly above that element. Then, account for the s-block, d-block, and p-block valence electrons. Copper has no p-block valence electrons, so in this question one must only consider s-block and d-block electrons. However, copper is one of several elements that allows one electron from the s-orbital to be held in the d-orbital. Thus, the correct electron configuration for copper is [Ar]4s¹3d¹⁰.

Question 8

Which of the following laws states that it is impossible to known the position and momentum of an electron simultaneously?
A)Pauli exclusion principle
B)Heisenberg's uncertainty principle
C)Hund's rule
D)Grahm's law
E)Ampere's law

Accepted Answer

Heisenberg's uncertainty principle states that it is impossible to known the position and momentum of an electron simultaneously. The act of determining the position of an electron changes that particle's momentum.

Question 9

What is the percentage carbon by mass of glucose, C₆H₁₂O₆? A)14.7 percent B)40.0 percent C)6)7 percent D)19.2 percent E)59.9 percent

Accepted Answer

To find the percentage carbon by mass in glucose, divide the mass of carbon in the compound by the total mass of the compound. This calculation is written (72.07 amu) / (180.15 amu), and indicates that glucose is 40.0 percent carbon by mass.

Question 10

What element has isotopes known as deuterium and tritium?
A)Bromine
B)Helium
C)Oxygen
D)Hydrogen
E)Chlorine

Accepted Answer

Hydrogen has isotopes known as deuterium and tritium. Protium, most common isotope of hydrogen, has one proton and no neutrons. Deuterium has one proton and one neutron, while tritium has one proton and two neutrons.

Quiz 2: Chemistry

Cu + 2AgNO₃--> 2Ag + Cu(NO₃)₂In the reaction above, which element is oxidized? A)Cu B)Ag C)N D)O E)Oxidation does not occur in this reaction

__CH₃OH(l) + _O₂(g) --> _CO₂(g) + ___H₂O(g)What set of coefficients correctly balances this equation? A)2, 3, 2, 1 B)1, 2, 2, 1 C)2, 3, 4, 2 D)2, 3, 3, 4 E)2, 3, 2, 4

2SO₂(g) + O₂(g) --> 2SO₃(g)What is the correct rate law for this reaction? A)r = k[SO₂][O₂] B)r = k[SO₃] C)r = k[SO₂]²[O₂] D)r = k[SO₃]² E)r = k[SO₃][SO₂][O₂]

80)0 grams of NaOH is dissolved in 3.0 moles of H?0. What is the mole fraction of NaOH in this solution? A))20 B))37 C))40 D))64 E))79

NH₃(g) + CuO(s) --> N₂(g) + Cu(s) + H₂O(g)What set of coefficients correctly balances the above equation? A)3, 3, 1, 2, 3 B)3, 2, 1, 2, 2 C)2, 3, 1, 3, 3 D)1, 2, 3, 2, 2 E)3, 2, 1, 2, 3

Which of the following elements displays bonding characterized by a delocalized "sea of electrons?" A)Fluorine B)Nitrogen C)Copper D)Sulfur E)Argon

Which of the following is the correct electron configuration for copper? A)[Ar] 4s²3d⁹ B)[Ar] 4s¹3d¹⁰ C)[Ar] 3s²3d⁹ D)[Ar] 3s¹3d¹⁰ E)[Kr] 4s²3d⁹

Which of the following laws states that it is impossible to known the position and momentum of an electron simultaneously? A)Pauli exclusion principle B)Heisenberg's uncertainty principle C)Hund's rule D)Grahm's law E)Ampere's law

What is the percentage carbon by mass of glucose, C₆H₁₂O₆? A)14.7 percent B)40.0 percent C)6)7 percent D)19.2 percent E)59.9 percent

What element has isotopes known as deuterium and tritium? A)Bromine B)Helium C)Oxygen D)Hydrogen E)Chlorine

Quiz 2: Chemistry

Cu + 2AgNO3--> 2Ag + Cu(NO3)2In the reaction above, which element is oxidized? A)Cu B)Ag C)N D)O E)Oxidation does not occur in this reaction

____CH3OH(l) + _____O2(g) --> _____CO2(g) + _____H2O(g)What set of coefficients correctly balances this equation? A)2, 3, 2, 1 B)1, 2, 2, 1 C)2, 3, 4, 2 D)2, 3, 3, 4 E)2, 3, 2, 4

2SO2(g) + O2(g) --> 2SO3(g)What is the correct rate law for this reaction? A)r = k[SO2][O2] B)r = k[SO3] C)r = k[SO2]2[O2] D)r = k[SO3]2 E)r = k[SO3][SO2][O2]

80)0 grams of NaOH is dissolved in 3.0 moles of H?0. What is the mole fraction of NaOH in this solution? A))20 B))37 C))40 D))64 E))79

NH3(g) + CuO(s) --> N2(g) + Cu(s) + H2O(g)What set of coefficients correctly balances the above equation? A)3, 3, 1, 2, 3 B)3, 2, 1, 2, 2 C)2, 3, 1, 3, 3 D)1, 2, 3, 2, 2 E)3, 2, 1, 2, 3

Which of the following elements displays bonding characterized by a delocalized "sea of electrons?" A)Fluorine B)Nitrogen C)Copper D)Sulfur E)Argon

Which of the following is the correct electron configuration for copper? A)[Ar] 4s23d9 B)[Ar] 4s13d10 C)[Ar] 3s23d9 D)[Ar] 3s13d10 E)[Kr] 4s23d9

Which of the following laws states that it is impossible to known the position and momentum of an electron simultaneously? A)Pauli exclusion principle B)Heisenberg's uncertainty principle C)Hund's rule D)Grahm's law E)Ampere's law

What is the percentage carbon by mass of glucose, C6H12O6? A)14.7 percent B)40.0 percent C)6)7 percent D)19.2 percent E)59.9 percent

What element has isotopes known as deuterium and tritium? A)Bromine B)Helium C)Oxygen D)Hydrogen E)Chlorine

Cu + 2AgNO₃--> 2Ag + Cu(NO₃)₂In the reaction above, which element is oxidized? A)Cu B)Ag C)N D)O E)Oxidation does not occur in this reaction

__CH₃OH(l) + _O₂(g) --> _CO₂(g) + ___H₂O(g)What set of coefficients correctly balances this equation? A)2, 3, 2, 1 B)1, 2, 2, 1 C)2, 3, 4, 2 D)2, 3, 3, 4 E)2, 3, 2, 4

2SO₂(g) + O₂(g) --> 2SO₃(g)What is the correct rate law for this reaction? A)r = k[SO₂][O₂] B)r = k[SO₃] C)r = k[SO₂]²[O₂] D)r = k[SO₃]² E)r = k[SO₃][SO₂][O₂]

NH₃(g) + CuO(s) --> N₂(g) + Cu(s) + H₂O(g)What set of coefficients correctly balances the above equation? A)3, 3, 1, 2, 3 B)3, 2, 1, 2, 2 C)2, 3, 1, 3, 3 D)1, 2, 3, 2, 2 E)3, 2, 1, 2, 3

Which of the following is the correct electron configuration for copper? A)[Ar] 4s²3d⁹ B)[Ar] 4s¹3d¹⁰ C)[Ar] 3s²3d⁹ D)[Ar] 3s¹3d¹⁰ E)[Kr] 4s²3d⁹

What is the percentage carbon by mass of glucose, C₆H₁₂O₆? A)14.7 percent B)40.0 percent C)6)7 percent D)19.2 percent E)59.9 percent