Q&A Hero

Q: For the following equilibrium reaction, which cause and effect are correctly matched?CO(g) + 2H2(g) -> CH3OH(g) + heatA) add heat, shift rightB) add CO, shift leftC) remove CH3OH, shift leftD) remove heat, no changeE) remove H2, shift left

Q: For the following reaction, the equilibrium constant Kc is 0.60 at a certain temperature. If the concentration of NO(g) and NOBr(g) are both 0.50 M,at equilibrium, what is the concentration of Br2(g)?2NO(g) + Br2(g) -> 2NOBr(g)A) 1.7 MB) 0.60 MC) 0.36 MD) 2.8 ME) 1.0 M

Q: For the following reaction, the equilibrium constant Kc is 2.0 at a certain temperature. If the concentration of both products is 0.10 M at equilibrium, what is the concentration of the starting material, NOBr?2NOBr(g) -> 2NO(g) + Br2(g)A) 5 10-4 MB) 2.2 10-4 MC) 5 10-2 MD) 2.2 10-2 ME) 2.2 M

Q: Carbon monoxide binds to hemoglobin 140 times more strongly than oxygen does. What does this tell you about the equilibrium constants for the two reactions of hemoglobin with carbon monoxide and oxygen? A) The equilibrium constant for the binding of CO is greater. B) The equilibrium constant for the binding of oxygen is greater. C) The concentration of carbon monoxide at equilibrium is twice that of oxygen. D) Oxygen and carbon monoxide have the same formula mass. E) Oxygen and carbon monoxide react with hemoglobin in different fashions.

Q: The value of the equilibrium constant for the combination of nitrogen and oxygen to make NO is 2 10-9. What does this tell you about the concentrations of materials in the equilibrium mixture? A) The concentration of products exceeds the concentration of reactants. B) The concentrations of reactants and products are equal. C) The reactants are solids. D) The concentration of reactants exceeds the concentration of products. E) The products are solids.

Q: Which of the following equilibrium constants indicates the reaction that gives the smallest amount of product? A) Kc = 5 10-10 B) Kc = 5 10-1 C) Kc = 5 100 D) Kc = 5 101 E) Kc = 5 1010

Q: The equilibrium constant for the production of carbon dioxide from carbon monoxide and oxygen is Kc = 2 1011. This means that the reaction mixture at equilibrium is likely to consist of A) mostly starting materials. B) an equal mixture of products and reactants. C) twice as much starting material as product. D) twice as much product as starting material. E) mostly products.

Q: In the following gas phase reaction, Kc is much less than 1. At equilibrium, which of the following statements is true?COCl2(g) -> CO(g) + Cl2(g)A) The concentration of reactant is much greater than the concentration of products.B) The concentration of products is much greater than the concentration of reactants.C) The concentrations of products and reactants are approximately equal.D) A catalyst will increase the concentration of products formed.E) At equilibrium, the concentrations of reactants and products are equal.

Q: The equilibrium for the reaction for the decomposition of PCl5 to chlorine and PCl3 is 0.042.PCl5(g) -> PCl3(g)+ Cl2(g)If the equilibrium concentrations are [PCl3] = 0.010 M, [Cl2] = 0.10 M, what is the value of [PCl5]?A) 0.010 MB) 0.0020 MC) 0.042 MD) 0.024 ME) 0.0010 M

Q: For the following reaction, the equilibrium concentration of NO2 is 0.38 M and equilibrium concentration of N2O4 is 1.0M. What is the value of the equilibrium constant?2NO2(g) -> N2O4(g)A) 0.14B) 2.6C) 6.9D) 0.38E) 1.0

Q: An equilibrium in which all the components are gases is a ________ equilibrium. A) heterogeneous B) liquid C) catalytic D) homogeneous E) reversible

Q: What is the correct form of the equilibrium constant for the reaction of hydrogen and oxygen to form water? The equation is:2H2(g) + O2(g) -> H2O(g)A) Kc = B) Kc = C) Kc = D) Kc = E) Kc =

Q: What is the correct form for the equilibrium constant expression for this reaction? H2(g) + F2(g) ⇌ 2HF(g) A) B) C) D) E)

Q: The reaction for the decomposition of PCl5 to chlorine and PCl3 is shown below.PCl5(g) -> PCl3(g) + Cl2(g)If the equilibrium concentrations are [PCl5] = 1.0 M, [PCl3] = 0.10 M, [Cl2] = 0.10 M, what is the value of the equilibrium constant?A) 1.0 10-2B) 1.0 10-4C) 10 10-2D) 1.0 102E) 2.0 10-2

Q: The equation for the formation of ammonia from nitrogen and hydrogen is shown below. What is the form of the equilibrium constant?3H2(g) + N2(g) -> 2NH3(g)A) B) C) D) E)

Q: When a reaction is at equilibrium, A) all reaction stops. B) no more reactants are converted to products. C) the reaction is no longer reversible. D) the forward and reverse reactions occur at the same rate. E) the products and reactants have the same energy content.

Q: A chemical reaction has reached equilibrium when A) the concentrations of reactants and products are equal. B) all reactants have been converted to products. C) all products have been removed from the reaction mixture. D) the catalyst has been used up. E) the rate of the forward reaction equals the rate of the reverse reaction.

Q: A reaction that can proceed in either the forward or the reverse direction as written is called a ________ reaction. A) reversible B) miniscule C) microscopic D) solid phase E) favored

Q: In the reaction of nitrogen and hydrogen to give ammonia, all the reactants and products are A) gases. B) liquids. C) solids. D) boiling. E) frozen.

Q: One metal that is used as a catalyst in a catalytic converter in an automobile is A) carbon. B) iron. C) copper. D) platinum. E) plutonium.

Q: In a catalytic converter in an automobile, the reaction of carbon monoxide with oxygen produces A) carbon dioxide. B) carbon and more oxygen. C) water. D) methane. E) nitrogen oxide.

Q: Refrigerating perishable foods affects biochemical reactions by A) increasing concentrations of antioxidants. B) removing bacteria. C) decreasing the rate of reactions affecting spoilage. D) catalyzing the removal of harmful chemicals from the foods. E) improving the appearance of the foods.

Q: In any chemical reaction, the rate of the reaction can be increased by A) decreasing the temperature. B) changing the size of the container. C) adding water to the reaction. D) adding product molecules to the reaction mixture. E) increasing the concentrations of the reactants.

Q: The rate of any chemical reaction can be determined by observing A) the amount of product formed in a unit of time. B) the ratio of product concentration to reactant concentration. C) the percent composition of the final product. D) the theoretical yield of the reaction. E) the number of chemical bonds broken and remade.

Q: In a catalyzed chemical reaction, one function of a catalyst is to A) increase the number of successful reactant collisions. B) decrease the concentration of reactants. C) change the equilibrium concentrations of the products and reactants. D) increase the energy given off during the reaction. E) increase the temperature at which the reaction is carried out.

Q: The activation energy of a chemical reaction is the energy that A) must be removed from the mixture. B) must be released from the mixture. C) initiates the reaction. D) activates the catalyst. E) is the difference in the energies of the starting materials and products.

Q: A catalyst is A) a reactant in a chemical reaction. B) a product in a chemical reaction. C) a substance that speeds up a reaction without being consumed in the reaction. D) a substance that increases the energy of the products. E) a substance that decreases the energy of the products.

Q: Identify the term defined in each description. A) hypotonic B) hydrogen bonding C) unsaturated D) hypertonic E) saturated F) hydration 1> a solution that contains the highest amount of solute that dissolves at a given temperature 2> the major attraction between water molecules 3> the association of several water molecules with ions produced in a solution 4> a solution in which more solute can be dissolved 5> a solution that has a higher osmotic pressure than the red blood cells of the body

Q: Substances whose particles in solution scatter light and pass through filters but cannot pass through semipermeable membranes are called ________.

Q: If 25.0 mL of a 0.800 M KCl solution is diluted to a final volume of 100. mL, the new concentration is ________.

Q: The number of moles of a compound dissolved in one liter of a solution is called the ________.

Q: In the following equation, ________ will form a precipitate.BaCl2 + H2SO4 -> BaSO4 + 2HCl

Q: In the following equation, ________ will form a precipitate.NaCl + AgNO3 -> AgCl + NaNO3

Q: Is barium sulfate, BaSO4, soluble or insoluble in water?

Q: A solution of sodium carbonate, Na2CO3, that has a molarity of 0.0100 M contains ________ equivalents of sodium ions per liter of the solution.

Q: A solution of sodium carbonate, Na2CO3, that has a molarity of 0.0100 M contains ________ equivalents of carbonate per liter of the solution.

Q: A substance that produces only a small number of ions in solution is known as a ________ electrolyte.

Q: A substance that carries an electric current when dissolved in water is called a(n) ________.

Q: A mixture in which one component settles is called a(n) ________. A) solution B) colloid C) suspension D) electrolyte E) nonelectrolyte

Q: Using a kidney machine to remove waste products from the blood is known as ________. A) osmosis B) osmolysis C) autolysis D) hemolysis E) hemodialysis

Q: If 100. mL of water is added to 25 mL of 5.0 M NaCl, the final concentration is ________. A) 25 M B) 1.0 M C) 5.0 M D) 2.0 M E) 1.3 M

Q: The molarity of a solution of 5.0 g of KCl in 100. mL of solution is ________. A) 0.038 M B) 0.067 M C) 0.67 M D) 0.13 M E) 1.3 M

Q: Methanol, CH3OH, can be classified as a ________. A) gas B) solid C) weak electrolyte D) strong electrolyte E) nonelectrolyte

Q: NaCl can be classified as a ________. A) gas B) liquid C) weak electrolyte D) strong electrolyte E) nonelectrolyte

Q: Acetic acid can be classified as a(n) ________. A) gas B) solid C) weak electrolyte D) strong electrolyte E) ionic compound

Q: What is the osmolarity of a solution made by dissolving 25.0 g of the strong electrolyte KCl in 1.0 L of solution? A) 0.168 Osm B) 0.335 Osm C) 0.250 Osm D) 0.670 Osm E) 1.34 Osm

Q: What is the osmolarity of a solution made by dissolving 0.50 mole of the strong electrolyte CaCl2 in 1.0 L of solution? A) 0.50 Osm B) 1.0 Osm C) 1.5 Osm D) 2.0 Osm E) 0.0 Osm

Q: 0.50 mole of NaCl is added to 1.0 kg of water. The freezing point of the solution will be ________. A) 0.00 C B) 0.93 C C) 1.86 C D) -0.93 C E) -1.86 C

Q: 0.50 mole of KCl is added to 2.0 kg of water. The boiling point of the solution will be ________ the boiling point of pure water. A) higher than B) lower than C) the same as

Q: 1.0 mole of NaCl is added to 1.0 kg of water. The freezing point of the solution will be ________ the freezing point of pure water. A) higher than B) lower than C) the same as

Q: An aqueous mixture containing starch (a colloid), NaCl, glucose, and albumin (a colloid) is placed in a dialyzing bag and immersed in distilled water. Which of the following correctly describes the location of the indicated substance after dialysis? A) albumin, inside B) starch outside C) albumin inside and outside D) water inside only E) starch inside and outside

Q: The process by which a semipermeable membrane allows water molecules, small molecules, and ions to pass through while retaining large particles is called A) osmotic pressure. B) dialysis. C) solvation. D) dilution. E) hydration.

Q: A red blood cell will undergo hemolysis in A) water. B) 0.9% NaCl. C) 5% glucose. D) 5% NaCl. E) 10% glucose.

Q: Which solution is isotonic to a red blood cell? A) water B) 0.5% NaCl C) 2% glucose D) 0.9% NaCl E) 10% glucose

Q: A red blood cell will undergo crenation in A) water. B) 0.5% NaCl. C) 3% glucose. D) 5% glucose. E) 7% NaCl.

Q: A solution that has an osmotic pressure less than that of red blood cells is called A) saturated. B) hypertonic. C) isotonic. D) hypotonic. E) unsaturated.

Q: A solution with the same osmotic pressure as the blood is A) isotonic to the blood. B) hypotonic to the blood. C) hypertonic to the blood. D) nontonic to the blood. E) molar to the blood.

Q: For the question that follow, consider a 4% starch solution and a 10% starch solution separated by a semipermeable membrane. Which of the following occurs in this system? A) Water flows equally in both directions. B) There is a net flow of water from the 4% starch solution into the 10% starch solution. C) There is a net flow of water from the 10% starch solution into the 4% starch solution. D) Water does not cross the membrane at all. E) Starch moves out of the 10% starch solution into the 4% starch solution.

Q: For the question that follow, consider a 4% starch solution and a 10% starch solution separated by a semipermeable membrane. The process that occurs in this system is A) filtration. B) hydration. C) neutralization. D) dialysis. E) osmosis.

Q: For the question that follow, consider a 4% starch solution and a 10% starch solution separated by a semipermeable membrane. Which starch solution will decrease in volume as osmosis occurs? A) 4% B) 10% C) Neither exerts osmotic pressure. D) They exert equal osmotic pressures. E) They exert opposite osmotic pressures.

Q: In the process known as osmosis, ________ moves through a semipermeable membrane into an area of ________ concentration. A) solute; lower solute B) solute; higher solute C) solvent; lower solute D) solvent; lower solvent E) solvent; higher solvent

Q: A homogeneous mixture that does not settle out upon standing is A) an element. B) a colloid. C) a suspension. D) homogeneous. E) hydrated.

Q: What is the new mass/volume (m/v)% of a KOH solution that is prepared by diluting 110 mL of a 6% (m/v) KOH solution to 330 mL? A) 2% B) 1% C) 6% D) 12% E) 18%

Q: What volume of a 2.00 M KCl solution is required to prepare 500. mL of a 0.100 M KCl solution? A) 0.0400 mL B) 25.0 mL C) 2.00 mL D) 1.00 104 mL E) 5.00 102 mL

Q: What volume of 0.10 M NaOH can be prepared from 250. mL of 0.30 M NaOH? A) 0.075 L B) 0.25 L C) 0.75 L D) 0.083 L E) 750 L

Q: What volume of 2.5% (m/v) KOH can be prepared from 125 mL of a 5.0% KOH solution? A) 0.0040 mL B) 63 mL C) 0.10 mL D) 125 mL E) 250 mL

Q: What is the molarity of a KCl solution made by diluting 75.0 mL of a 0.200 M solution to a final volume of 100. mL? A) 0.267 M B) 0.150 M C) 0.200 M D) 6.67 M E) 0.100 M

Q: During the process of diluting a solution to a lower concentration, A) the amount of solute does not change. B) the amount of solvent does not change. C) there is more solute in the concentrated solution. D) the volume of the solution does not change. E) water is removed from the concentrated solution.

Q: Use the reaction: 2AgNO3(aq) + H2SO4(aq) -> Ag2SO4(s) + 2H2O(l).What volume of 0.123 M AgNO3(aq) is needed to form 0.657 g of Ag2SO4(s)?A) 34.2 LB) 17.1 mLC) 34.3 mLD) 10.7 mLE) 53.4 mL

Q: How many mL of 0.246 M Pb(NO3)2 are needed to react with 36.0 mL of 0.322 M KCl ?2KCl(aq) + Pb(NO3) 2(aq) -> 2KNO3(aq) + PbCl2(s)A) 36.0 mLB) 18.0 mLC) 72.0 mLD) 47.1 mLE) 23.6 mL

Q: How many grams of PbCl2 are formed when 25.0 mL of 0.654 M KCl react with Pb(NO3)2?2KCl(aq) + Pb(NO3) 2(aq) -> 2KNO3(aq) + PbCl2(s)A) 22.7 gB) 1.64 gC) 2.27 gD) 4.54 gE) 9.08 g

Q: What volume of a 1.5 M KOH solution is needed to provide 3.0 moles of KOH? A) 3.0 L B) 0.50 L C) 2.0 L D) 4.5 L E) 0.22 L

Q: How many moles of CaCl2 are in 250 mL of a 3.0 M of CaCl2 solution? A) 750 moles B) 1.3 moles C) 83 moles D) 0.75 mole E) 3.0 moles

Q: What is the molarity of a solution which contains 58.5 g of sodium chloride dissolved in 0.500 L of solution? A) 0.500 M B) 1.00 M C) 1.50 M D) 2.00 M E) 4.00 M

Q: What is the molarity of a solution containing 5.0 moles of KCl in 2.0 L of solution? A) 2.5 M B) 1.0 M C) 5.0 M D) 10. M E) 2.0 M

Q: The molarity (M) of a solution refers to A) moles of solute/L of solution. B) moles of solute/L of solvent. C) moles of solute/100 mL of solution. D) grams of solute/100 mL of solution. E) grams of solute/L of solution.

Q: When 200. mL of water are added to 100. mL of 12% KCl solution the final concentration of KCl is (Assume the volumes add.) A) 12%. B) 4.0%. C) 36%. D) 6.0%. E) 8.0%.

Q: What is the molarity of a solution that contains 3.25 moles of NaNO3 in 250. mL of solution? A) 3.25 M B) 6.50 M C) 0.0130 M D) 13.0 M E) 2.60 M

Q: What is the molarity of a solution that contains 17 g of NH3 in 0.50 L of solution? A) 34 M B) 2.0 M C) 0.50 M D) 0.029 M E) 1.0 M

Q: How many milliliters of a 25% (m/v) NaOH solution would contain 75 g of NaOH? A) 25 mL B) 75 mL C) 33 mL D) 19 mL E) 3.0 102 mL