Chemistry Released Final

A neutral atom has a ground state electron configuration of 1s22s22p63s2. The neutral atom becomes an ion during a chemical reaction. Which is the most likely charge of the ion? A) 2+ B) 1+ C) 2- D) 6-

A) 2+

In a hypothetical reaction, reactants X and Y are combined in an evacuated vessel and allowed to come to equilibrium with product Z at a temperature of 200K. X (g) + Y (g) → Z (g) After equilibrium is established, the temperature is slowly raised, and additional values of Keq are determined as shown in this data table: (ADD TABLE) Which temperature has the greatest concentration of product Z? A) 200K B) 300K C) 400K D) 500K

A) 200K

A phase diagram is shown below. (ADD GRAPH) Which choice describes the state of the substance at X? A) A boiling liquid is in equilibrium with its vapor. B) A subliming solid is in equilibrium with its vapor. C) A freezing liquid is in equilibrium with its solid. D) A melting solid is in equilibrium with its liquid.

A) A boiling liquid is in equilibrium with its vapor.

Which statement best compares how bond strengths affect the physical properties of iron and lead? A) Iron has a higher melting point because the bonds in iron are stronger. B) Iron has a higher melting point because the bonds in iron are weaker. C) Lead has a higher density because the bonds in lead are stronger. D) Lead has a higher density because the bonds in lead are weaker.

A) Iron has a higher melting point because the bonds in iron are stronger.

Which type of bonding or intermolecular forces is/are weakest? A) London dispersion forces B) hydrogen bonding C) dipole-dipole forces D) covalent bonding

A) London dispersion forces

Which group of elements is arranged in order of increasing atomic radii? A) O,S,Se,Te B) Fe, Ni, Ag, Au C) Rb, K, Na, Li D) Y, Zr, Nb, Mo

A) O,S,Se,Te

Which statement describes equilibrium between liquid water and water vapor? A) The rate of vaporization equals the rate of condensation. B) The rate of vaporization is greater than the rate of condensation. C) The rate of vaporization equals the rate of sublimation. D) The rate of vaporization is greater than the rate of sublimation.

A) The rate of vaporization equals the rate of condensation.

The equation below represents the radioactive decay of a gold isotope. 174Au → 170Ir + ? 79 77 (ADD EQUATION) Which choice correctly completes this equation? A) alpha particle B) beta particle C) photon D) neutron

A) alpha particle

What type of solution is formed when solid sodium hydroxide (NaOH) is dissolved in water? A) an electrolytic solution, because NaOH will dissociate into ions B) an electrolytic solution, because NaOH will not dissociate into ions C) a nonelectrolytic solution, because NaOH will dissociate into ions D) a nonelectrolytic solution, because NaOH will not dissociate into ions

A) an electrolytic solution, because NaOH will dissociate into ions

Which element will form covalent bonds with chlorine? A) carbon B) aluminum C) magnesium D) potassium

A) carbon

The chemical equation below represents a reaction at equilibrium in a closed flask. Which action will cause the reaction to shift to the left? A) heating the flask with a hot plate B) placing the flask in an ice bath C) removing H2O from the flask D) adding CO to the flask

A) heating the flask with a hot plate

An acid-base titration is represented by the chemical equation below. CsOH (aq) + HBr (aq) → CsBr (aq) + H2O (l) In the titration, 15.0 mL of CsOH solution is neutralized by 38.2 mL of 0.250 M HBr solution. What is the molarity of the CsOH solution? A) 0.0982 M B) 0.637 M C) 1.36 M D) 10.2 M

B) 0.637 M

A chemical equation is shown below. CaSO4 + AlBr3 → CaBr2 + Al2(SO4)3 What will be the coefficient of CaBr2 when the equation is balanced using the smallest possible whole-number coefficients? A) 2 B) 3 C) 4 D) 5

B) 3

How many electrons are in the outermost energy level of a neutral carbon atom? A) 2 B) 4 C) 6 D) 8

B) 4

A neutral atom of a certain element has the electron configuration 1s22s22p63s23p4. How many valence electrons does the atom have? A) 4 B) 6 C) 11 D) 16

B) 6

A student experimented with magnesium ribbon and hydrochloric acid. • The student placed a piece of solid magnesium ribbon in a test tube containing hydrochloric acid solution. • The student observed that vigorous bubbling occurred. • The student collected some of the gas generated by the bubbles in a test tube. • The student tested the gas produced with a burning wood splint, which ignited quickly with a popping sound. What can the student conclude about the experiment? A) A chemical reaction occurred because new atoms were created. B) A chemical reaction occurred because a new substance was formed. C) The popping sound provided evidence that the acid changed physical states. D) The popping sound provided evidence that the magnesium atoms were destroyed.

B) A chemical reaction occurred because a new substance was formed.

What is the molecular formula of a compound with the empirical formula CH2O and a molecular mass of 60 g/mol? A) CH2O B) C2H4O2 C) C2H4O4 D) C2H2O2

B) C2H4O2

A potential energy diagram of a chemical reaction is shown below. (ADD GRAPH) Which choice would be changed by the addition of a catalyst to the reaction? A) R B) S C) T D) U

B) S

An equilibrium is established between substances W, X, Y, and Z. W+X Y+Z How would the conditions of equilibrium be affected by decreasing the concentration of substance W? A) Substances X and Y would react to replace substance W, and the position of equilibrium would shift to the right. B) Substances Y and Z would react to replace substance W, and the position of equilibrium would shift to the left. C) This would increase pressure, causing only substance Y to replace substance W and shifting the equilibrium to the right. D) This would decrease temperature, causing only substance Z to replace substance W and shifting the equilibrium to the left.

B) Substances Y and Z would react to replace substance W, and the position of equilibrium would shift to the left.

A phase diagram is shown below. (ADD GRAPH) What is the condition of the sample at point X? A) The sample is in a gaseous state. B) The sample is in a liquid state. C) The sample is at its critical point. D) The sample is at its triple point.

B) The sample is in a liquid state.

Which statement explains what happens when potassium chloride (KCl) dissolves in water? A) Water molecules surround the potassium chloride but do not exert forces of attraction strong enough to break any bonds. B) Water molecules exert forces of attraction that break the potassium chloride apart into potassium ions and chloride ions. C) Water molecules exert forces of attraction that break the potassium chloride apart into neutral atoms of potassium and neutral atoms of chlorine. D) Water molecules exert forces of attraction that break the potassium chloride apart into potassium atoms and diatomic chlorine gas.

B) Water molecules exert forces of attraction that break the potassium chloride apart into potassium ions and chloride ions.

A 2.0-liter closed container holds 1.0 mole of an ideal gas at a certain temperature and pressure. Which closed container will hold 3.0 moles of this ideal gas at the same temperature and pressure? A) a 3.0-liter container B) a 6.0-liter container C) a 9.0-liter container D) a 12.0-liter container

B) a 6.0-liter container

The student places a liquid as a slippery. The student places red litmus paper into the liquid, and the paper turns blue. What can the student conclude from these observations? A The substance is likely a nonmetal. B The substance is likely a metal. C The substance is likely a base. D The substance is likely an acid.

C The substance is likely a base.

What is the chemical formula for chromium(III) oxide? A) CrO B) CrO2 C) Cr2O3 D) Cr3O2

C) Cr2O3

A student conducts the following demonstration: • A 15-g sample of NaHCO3 is placed in a test tube. • The bottom of the test tube is heated with an open flame. • Condensation forms on the inside walls of the test tube. • A burning splint is extinguished when placed at the mouth of the test tube. What can the student conclude after conducting this demonstration? A) The burning splint was extinguished because of a lack of CO2 in the test tube. B) The burning splint was extinguished because of a lack of H2O vapor. C) Decomposition produced CO2 and H2O. D) Combustion produced O2 and H2O.

C) Decomposition produced CO2 and H2O.

A solution has a pOH of 12. Which best describes the solution? A) IthasapHof2andisabase. B) IthasapHof12andisabase. C) IthasapHof2andisanacid. D) IthasapHof12andisanacid.

C) IthasapHof2andisanacid.

Which three elements are arranged according to increasing electronegativity values? A) N,C,B B) N,P,As C) N,O,F D) F,O,N

C) N,O,F

How is copper (Cu) classified based on its location on the periodic table? A) a nonmetal B) an alkaline earth metal C) a transition metal D) an alkali metal

C) a transition metal

What is the name of the compound with the chemical formula CoF3? A) fluorocobalt B) cobalt trifluoride C) cobalt(III) fluoride D) fluorine(III) cobalt

C) cobalt(III) fluoride

A sample of metal has a mass of 5.2 g and absorbs 20.0 J of energy as it is heated from 30.0°C to 40.0°C. What is the identity of the metal? A) iron B) gold C) copper D) magnesium

C) copper

The diagram below shows the solubility of sugar in water. (ADD GRAPH) A student dissolves 300 g of sugar in 100 g of water at 80°C. The solution is then allowed to cool to 40°C. The appearance of the solution does not change during the cooling. Which term accurately describes the solution at 40°C? A) suspension B) colloid C) supersaturated D) unsaturated

C) supersaturated

The equation below represents a chemical reaction. Zn (s) + 2HCl (aq) → ZnCl2 (aq) + H2 (g) A 5.00-g sample of zinc is added to hydrochloric acid. The amount of hydrochloric acid is sufficient to allow the zinc to react completely. What mass of hydrogen gas does this reaction produce? A) 0.0308 g B) 0.0771 g C) 0.121 g D) 0.154 g

D) 0.154 g

How many O2 particles are in 2.50 moles of O2 at Standard Temperature and Pressure (STP)? A) 4.15 × 1022 particles B) 2.41 × 1023 particles C) 5.02 × 1023 particles D) 1.51 × 1024 particles

D) 1.51 × 1024 particles

What is the approximate temperature of 1.4 moles of a gas with a pressure of 3.25 atmospheres in a 4.738-liter container? A) 180 K B) 170 K C) 150 K D) 130 K

D) 130 K

The table below shows the electron configurations of three elements. Element (ADD TABLE) Electron Configuration Element 1 1s22s22p2 Element 2 1s22s22p5 Element 3 1s22s22p4 What is the order of the elements from smallest to largest atomic radius? A) Element 1, Element 2, Element 3 B) Element 1, Element 3, Element 2 C) Element 2, Element 1, Element 3 D) Element 2, Element 3, Element 1

D) Element 2, Element 3, Element 1

Which isotope has the greatest number of protons? A) Pa-238 B) U-240 C) Np-238 D) Pu-239

D) Pu-239

Test results on two white crystalline solids are shown in the table below: (ADD TABLE) Based on the information in the table, what can be concluded? A) Both solids contain only ionic bonds. B) Both solids contain only covalent bonds. C) Solid X contains only covalent bonds, and Solid Y contains only ionic bonds. D) Solid X contains only ionic bonds, and Solid Y contains only covalent bonds.

D) Solid X contains only ionic bonds, and Solid Y contains only covalent bonds.

The compound sodium chloride is placed in water and separates into ions. What are the correct names for these ions? A) The chloride and sodium ions are cations. B) The chloride and sodium ions are anions. C) The sodium ion is the anion, and the chloride ion is the cation. D) The sodium ion is the cation, and the chloride ion is the anion.

D) The sodium ion is the cation, and the chloride ion is the anion.

Why does an increase in temperature usually increase the rate of a chemical reaction? A) because the activation energy of the reaction increases B) because the surface area of reacting particles increases C) because the proper orientation of reacting particles improves D) because the number of effective collisions between reacting particles increases

D) because the number of effective collisions between reacting particles increases

What color of light does a hydrogen atom emit when an electron transitions from the n=6 energy level to the n=2 energy level? A) orange B) yellow C) blue D) violet

D) violet