Chemistry 101 Final Ivy Tech

A balloon originally had a volume of 0.439 L at 44C and a pressure of 729 torr. To what temperature must the balloon be cooled to reduced its volume to 378 mL if the pressure remained constant? A. 0 C B. 38 C C. 95 C D. 272 C E. none of the above

A

Boyle's Law is expressed as: A. V is proportional to 1/P B. P is proportional to V C. V is proportional to 1/T D. V is proportional to T E. none of the above

A

Calculate the maximum number of grams of NH3 that can be produced by the reaction of 2.00 g of N2 with 3.00 g of H2. Reaction: N2 (g) + 3H2 (g) ⟶ 2 NH3 (g) A. 2.43 B. 0.964 C. None of the above D. 4.00 E. 17.0

A

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

Diatomic N2 can react with diatomic H2 to form ammonia (NH3). The balanced chemical equation is: N2 + 3 H2 ⟶ 2 NH3 If 6 moles of H2 totally reacted with more than enough N2, how many moles of ammonia would be expected to form? A. 4 Moles B. 6 Moles C. 3 Moles D. 2 Moles E. Not enough info

A

In order for a solute to dissolve in a solution: A. The solute-solvent forces must be greater than the solute-solute forces B. The solute-solute forces must be greater than the solute-solvent forces C. The solute-solvent forces must equal the solute-solute forces D. The polarity of the solute and solvent must be opposite E. None of the above

A

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

What is the equivalent of 960 mm Hg in units of atm? A. 1.27 atm B. 0.785 atm C. 968 atm D. 1.30 atm E. none of the above

A

What is the final pressure (expressed in atm) of a 3.05 L system initially at 724 mm Hg and 298 K, that is compressed to a final volume of 2.51 L at 273 K? A. 1.06 B. 1.60 C. 806 D. 860 E. none of the above

A

When filling orbitals of equal energy, electrons fill them singly first with parallel spins. This is known as: A. Hund's Rule B. Pauli Exclusion Principle C. Bohr's Model D. Ground State E. None of the above

A

Which element is represented by the electron configuration 1s22s22p2? A. C B. He C. Be D. O E. None of the above

A

A solution contains 100.0 g of water, 10.0 g NaCl, and 15.0 g methanol. What is the mass percent of methanol in the solution? A. 8.00% B. 10.00% C. 12.0% D. 15.0% E. none of the above

C

An accepted abbreviation format is to write an electron configuration that includes a noble gas symbol in brackets. If you were writing an electron configuration for a bromine atom, which elemental symbol would you place in the bracket? A. He B. Ne C. Ar D. Kr E. Xe

C

Chlorine and bromine have very similar chemical properties. This is best explained by the fact that both elements: A. Are gases B. Are in period 3 of the Periodic Table C. Have the same number of valence electrons D. Have equal number of protons and electrons E. None of the above

C

Diatomic O2 can react with the element magnesium to form magnesium oxide (MgO). The balanced chemical equation is: O2 + Mg ⟶ 2 MgO If 4 moles of magnesium totally reacted with more than enough O2, how many moles of MgO would be expected to form? A. 8 Moles B. 2 Moles C. 4 Moles D. 1 Mole E. Not Enough Info

C

How many moles of NH3 can be produced by the reaction of 2.00 g of N2 with 3.00 g H2? Reaction: N2 (g) + 3 H2 (g) ⟶ 2 NH3 (g) A. 1.00 B. 0.235 C. 0.143 D. 0.0567 E. None of the above

C

If each of the following gas samples have the same temperature and pressure, which sample has the greatest volume? A. 1 gram of 02 B. 1 gram of Ar C. 1 gram of H2 D. all have the same volume E. not enough information

C

The electronegativity value for N is 3.0 and that for O 3.5. Based on these values, which of the following statements is TRUE about the compound NO? A. NO is an ionic compound B. NO is a pure covalent compound C. NO is a polar covalent compound D. There is not enough information E. None of the above are true

C

What is the electron configuration for Kr? A. 1s22s22p63s23p43d104s24p6 B. 1s22s22p63s23p64s23d24p6 C. 1s22s22p63s23p64s23d104p6 D. 1s22s22p63s23p24s23d104p6 E. none of the above

C

What is the molecular geometry if you have 4 single bonds around the central atom? A. Bent B. Linear C. Tetrahedral D. Trigonal Pyramidal E. Not enough info

C

What is the molecular geometry of NH4+? A. bent B. linear C. tetrahedral D. trigonal pyramidal E. not enough info

C

What is the molecular geometry of SiH4? A. bent B. linear C. tetrahedral D. trigonal pyramidal E. not enough info

C

What is the volume of 28.0g of nitrogen gas at STP? A. 33.6 L B. 11.2 L C. 22.4 L D. 44.8 L E. none of the above

C

Which is the limiting reactant in the following reaction given that you start with 42.0 g of CO2 and 99.9 g KOH? Reaction: CO2+ 2 KOH ⟶ K2CO3 + H2O A. CO2 B. Not enough information C. KOH D. K2CO3 E. H2O

C

Which of the following statements about the quantum-mechanical model is FALSE? A. Orbitals are a probability map of finding electrons. B. Electrons do not behave as particles. C. Orbitals are specific paths electrons follow. D. Electron paths cannot be described exactly. E. All of the above are correct.

C

Which of the following statements about the water molecule is TRUE? A. A water molecule has two dipole moments and they cancel each other. B. A water molecule is symmetrical and therefore is non-polar. C. A water molecule is asymmetric and therefore is polar. D. The electronegativities of hydrogen and oxygen are equal and therefore a water molecule is non-polar. E. None of the above

C

Which symbol should be used between two structures that represent resonance structures? A. --------> B. <-------- C. <-------> D. =

C

A sample of helium gas initially at 37.0C, 785 torr and 2.00 L was heated to 58.0C while the volume expanded to 3.24 L. What is the final pressure in atm? A. 517 B. 0.681 C. 1.79 D. 3.21 E. none of the above

B

How many electrons are in a chlorine atom? A. 1 B. 17 C. 10 D. 7 E. None of the above

B

How many electrons can exist in an orbital? A. 1 B. 2 C. 3 D. 4 E. None of the above

B

How many grams of the excess reactant remain assuming the reaction goes to completion and that you start with 15.5 g of Na2S and 12.1 g of CuSO4? Reaction: Na2S+ CuSO4 ⟶ Na2SO4 + CuS A. 0.05 B. 9.58 C. 5.92 D. 15.45

B

How many moles of chlorine gas are needed to make 0.6 moles of sodium chloride? Given the reaction: 2 Na + Cl2 ⟶ 2NaCl A. 3.6 B. 0.3 C. 1.2 D. 0.6 E. Not enough info

B

How many moles of lithium nitrate are theoretically produced if we start with 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4? Reaction: 3 Ca(NO3)2 + ⟶ 6LiNO3 + Ca3(PO4)2 A. 1.1 B. 6.8 C. 1.2 D. Not enough info E. 7.2

B

Hydrochloric acid reacts with barium hydroxide according to the equation: 2 HCl (aq) + Ba(OH)2 (aq) ⟶ BaCl2 (aq) + 2 H2O ( l) Δ H= -118 kK Calculate the heat (in kJ) associated with the complete reaction of 18.2 grams of HCl (aq). A. -58.9 B. -29.5 C. None of above D. -236 E. +58.9

B

Hydrogen gas produced in the laboratory by the reaction of zinc and hydrochloric acid was collected over water at 25C. The barometric pressure at the time was 742.5 mm Hg. What is the pressure of dry hydrogen gas if the vapor pressure of water at 25C is 23.8 mm Hg? A. 742.5 mmHg B. 718.7 mmHg C. 766.3 mmHg D. 760.0 mmHg E. None of the above

B

If the electron configuration of a ground state sodium atom is 1s22s22p63s1, the electron configuration of the sodium cation (Na+) would be: A. 1s2 2s2 2p6 3s2 B. 1s2 2s2 2p2 C. 1s2 2s2 2p6 3s1 D. 1s1 2s2 2p1 3s1

B

The Lewis model predicts that the formula for a compound between Potassium and Sulfur is: A. KS B. K2S C. KS2 D. K3S E. None of the above

B

The subshell that has three orbitals and can hold up to six electrons is the: A. S subshell B. P subshell C. D subshell D. F subshell E. None of the above

B

What is the electron configuration for Ga? A. 1s22s22p63s23p63d104s24p6 B. 1s22s22p63s23p64s23d104p1 C. 1s22s22p63s23p53d104s24p1 D. 1s22s22p63s23p64s24d104p1 E. None of the above

B

What is the limiting reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of Li3PO4? Reaction: 3Ca(NO3)2 + 2Li3PO4 ⟶ 6LiNO3 + Ca3(PO4)2 A. Ca3(PO4)2 B. Ca(NO3)2 C. Li3PO4 D. LiNO3

B

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

B

Which of the following is TRUE? A. Stoichiometry allows prediction of how much of the reactants are necessary to form a given amount of product. B. All of the above are true. C. Stoichiometry allows prediction of the amount of products that form in a chemical reaction based on the amounts of reactants. D. Stoichiometry shows the numerical relationship between chemical quantities in a balanced chemical equation.

B

Charle's Law is expressed as: A. V is proportional to 1/P B. P is proportional to V C. V is proportional to 1/T D. V is proportional to T E. none of the above

D

How many electrons are unpaired in the orbitals of nitrogen? A. 14 B. 5 C. 9 D. 3 E. None of the above

D

How many liters of O2 (g) are needed to react completely with 56.0 L of CH4 (g) at STP to produced CO2 (g) and H2O (g)? Given: CH4 (g) + 2 O2 (g) ⟶ CO2 (g) + H2O (g) A. 28.0 L B. 56.0 L C. 84.0 L D. 112.0 L E. none of the above

D

How many subshells are there in the n=4 principal shell? A. 1 B. 2 C. 3 D. 4 E. Not enough info

D

If a mixture of gases contained 78% nitrogen at a pressure of 984 torr and 22% carbon dioxide at 345 torr, what is the total pressure of the system? A. 1,329 atm B. 17.5 cm Hg C. 639 torr D. 1.75 atm E. none of the above

D

If the volume of a gas container at 32.0 C changes from 1.55 L to 755 mL, what will the final temperature be? A. 149 C B. 353 C C. 273 C D. -124 C E. none of the above

D

The "d" subshell can hold a maximum of ______ electrons. A. 2 B. 5 C. 6 D. 10 E. None of the above

D

The principal quantum number (n): A. Specifies the 3-D shape of the orbital B. Specifies the principal quantum number of the orbital. C. Specifies the maximum number of electrons. D. Specifies the principal shell of the orbital. E. None of the above.

D

The reaction of one mole of nitrogen gas with three moles of hydrogen gas releases 92 kJ of thermal energy to the surroundings. Which of the following is TRUE? A. None of the above are true B. This reaction is exothermic C. This reaction has a negative enthalpy of reaction D. All of the above are true E. Complete reaction of two moles of nitrogen gas would release 184 kJ of thermal energy in this reaction.

D

The solubility of a gas in a liquid can always be increased by: A. increasing the temperature of the solvent B. decreasing the polarity of the solvent C. decreasing the pressure of the gas above the solvent D. increasing the pressure of the gas above the solvent E. none of the above

D

The total number of electrons to be counted for the Lewis structure of PO4- polyatomic ion is: A. 8 B. 26 C. 29 D. 32 E. none of the above

D

What is the molecular geometry if you have 3 single bonds and 1 lone pair around the central atom? A. bent B. linear C. tetrahedral D. trigonal pyramidal E. not enough info

D

What is the molecular geometry of PH3? A. bent B. linear C. tetrahedral D. trigonal pyramidal E. not enough info

D

Which of the following is NOT part of the Kinetic Molecular Theory? A. Gas particles do not repel each other. B. There is a large distance between gas particles as compared to their relative size. C. The size of the actual gas particles is small compared to the volume of the whole gas. D. The average energy of the particles is dependent on the molecular mass of the particle. E. All of the above are true.

D

Which of the following statements are TRUE about the BF3 molecule? A. BF3 has a trigonal planar molecular geometry B. BF3 violates the octet rule for the central atom C. BF3 is nonpolar D. All of the above statements are true E. None of the above are true

D

Consider the following electronegativity values: H=2.1, Cl=3.0, F=4.0 Which molecule below would you expect to have the more polar bond? A. H2 B. Cl2 C. F2 D. HCl E. HF

E

Consider the following reaction: 2 Mg + O2 ⟶ 2 MgO Δ Hrxn = -1203 kJ. Calculate the amount of heat (in kJ) associated with complete reaction of 4 moles of Mg. A. -1203 kJ B. -601.5 kJ C. -4812 kJ D. None of the above E. -2406 kJ

E

How many grams of NO2 are theoretically produced if we start with 1.2 moles of S and 9.90 moles of HNO3? Reaction: S + 6HNO3 ⟶ H2SO4+ 6 NO3+ 2 H2O A. 455 B. Not enough info C. 7.20 D. 786 E. 331

E

How many moles of water are needed to react with 2.2 moles of Li2O? Given: Li2O + H2O ⟶ 2 LiOH A. None of the above B. 1.1 C. 4.4 D. 1.5 E. 2.2

E

Which of the following statements about pressure is FALSE? A. Pressure is caused by gas molecules colliding with surfaces. B. The atmosphere has a pressure as the components of air collide with surfaces. C. After creating a pressure difference, the atmosphere pressure can push liquid up a straw. D. A deep well dug in the ground must have the pump located at the bottom of the well in order to have water come to the surface. E. All of the above are true.

E

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

False

A correct Lewis structure of an atom of carbon would have eight dots surrounding the symbol of the element True False

False

If the theoretical yield of a reactant is 144 grams and the actual yield of the reaction is 72 grams, the percent yield of the reaction is 200%. True False

False

One mole of F2 gas at STP would take up twice the volume of one mole of Ar gas at STP. True False

False

The element manganese (Mn) has five valence electrons. True False

False

The higher the principle quantum number, the lower the orbital energy. True False

False

The main component of the air we breath is oxygen gas. True False

False

Using pure oxygen is scuba diving tanks is a good method of preventing the nitrogen bends. True False

False

When an atom absorbs energy, it often re-emits that energy as heat. True False

False

A sealed bag of potato chips will expand when taken to a higher altitude. This is an example of Boyle's Law. True False

True

Given the following generic equation, 2A +3B ⟶ A2B3 Δ Hrxn = +444 kJ, if you completely reacted 1 mole of compound A, the amount of heat absorbed would be 222 kJ. True False

True

Given the recipe: 2 cups flour + 1 egg + 3 oz blueberries ⟶ 4 muffins If you have 9 cups of flour, 4 eggs, and plenty of blueberries, the theoretical yield of muffins is 16 True False

True

Having eight valence electrons is very stable and is called an octet. True False

True

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

True

Resonance structures are the best representation we can draw but do not accurately reflect the true structure. True False

True

Since heat must be supplied to melt ice, the melting of ice is an endothermic process and so has a positive enthalpy value. True False

True

The early scientists who developed the quantum-mechanical model were bewildered by the model and it altered our fundamental view of matter. True False

True

The limiting reactant is not necessarily the reactant with the least mass. True False

True

Vapor pressure of water increases with increasing temperature because the higher temperature more water molecules to evaporate. True False

True

When the elements are arranged in order of increasing number of protons, certain sets of properties recur periodically. True False

True