PS.Ch6.Test.95 - cloudfront.net
... system, the process is said to be _______ and the sign of H is ________. a) exothermic, positive b) endothermic, negative c) exothermic, negative ...
... system, the process is said to be _______ and the sign of H is ________. a) exothermic, positive b) endothermic, negative c) exothermic, negative ...
EXAM 3 NAME____KEY –Answers highlighted______(1 pt.) Dr
... Pb(NO3)2(aq) + 2 NaBr(aq) → PbBr2(s) + 2 NaNO3(aq) this is the molecular equation From the solubility table lead bromide is insoluble which is why it has (s) after it. The sodium and nitrate ions will be spectator ions and cancel. a) Pb(NO3)2(aq) + 2 NaBr(aq) → PbBr2(aq) + 2 NaNO3(s) b) Na+(aq) + NO ...
... Pb(NO3)2(aq) + 2 NaBr(aq) → PbBr2(s) + 2 NaNO3(aq) this is the molecular equation From the solubility table lead bromide is insoluble which is why it has (s) after it. The sodium and nitrate ions will be spectator ions and cancel. a) Pb(NO3)2(aq) + 2 NaBr(aq) → PbBr2(aq) + 2 NaNO3(s) b) Na+(aq) + NO ...
Chemistry 2nd Semester Final Review
... 39. Draw an energy vs. reaction progress graph for each of the following types of reactions: endothermic, exothermic, and catalyzed reaction 40. List the factors that can affect reaction rates. Explain what happens to the reaction rate when these factors are changed. 41. What is true of each of the ...
... 39. Draw an energy vs. reaction progress graph for each of the following types of reactions: endothermic, exothermic, and catalyzed reaction 40. List the factors that can affect reaction rates. Explain what happens to the reaction rate when these factors are changed. 41. What is true of each of the ...
Chemistry EOC Review
... 325mm Hg to 550mm Hg, what is the new volume of the gas? 80) A sample of gas has a volume of 140.0mL at 67C. To what temperature must the gas be lowered to reduce its volume to 50.0 mL at constant pressure? 81) A sample of gas at 47C and 780.mm Hg pressure occupies a volume of 2.20L. What volume w ...
... 325mm Hg to 550mm Hg, what is the new volume of the gas? 80) A sample of gas has a volume of 140.0mL at 67C. To what temperature must the gas be lowered to reduce its volume to 50.0 mL at constant pressure? 81) A sample of gas at 47C and 780.mm Hg pressure occupies a volume of 2.20L. What volume w ...
Spring Benchmark Exam
... clear solution and set it aside on the lab bench. After several hours she noticed the solution had become cloudy and some solid had settled to the bottom of the flask. Which statement best describes what happened? A As the solution cooled, evaporation of water increased the KCl concentration beyond ...
... clear solution and set it aside on the lab bench. After several hours she noticed the solution had become cloudy and some solid had settled to the bottom of the flask. Which statement best describes what happened? A As the solution cooled, evaporation of water increased the KCl concentration beyond ...
File
... Alex’s hypothesis was that the rate will be affected by changing the concentrations of the propanone and the iodine, as the reaction can happen without a catalyst. Hannah’s hypothesis was that as the catalyst is involved in the reaction, the concentrations of the propanone, iodine and the hydrogen i ...
... Alex’s hypothesis was that the rate will be affected by changing the concentrations of the propanone and the iodine, as the reaction can happen without a catalyst. Hannah’s hypothesis was that as the catalyst is involved in the reaction, the concentrations of the propanone, iodine and the hydrogen i ...
Chapter 4
... KCl(aq) + Pb(NO3)2(aq) -> 2KCl(aq) + Pb(NO3)2(aq) -> PbCl2(s) + 2KNO3(aq) AgNO3(aq) + MgBr2(aq) -> 2AgNO3(aq) + MgBr2(aq) -> 2AgBr(s) + Mg(NO3)2(aq) Ca(OH)2(aq) + FeCl3(aq) -> 3Ca(OH)2(aq) + 2FeCl3(aq) -> 2Fe(OH)3(s) + 3CaCl2(aq) NaOH(aq) + HCl(aq) -> NaOH(aq) + HCl(aq) -> H2O(l) + NaCl(aq) ...
... KCl(aq) + Pb(NO3)2(aq) -> 2KCl(aq) + Pb(NO3)2(aq) -> PbCl2(s) + 2KNO3(aq) AgNO3(aq) + MgBr2(aq) -> 2AgNO3(aq) + MgBr2(aq) -> 2AgBr(s) + Mg(NO3)2(aq) Ca(OH)2(aq) + FeCl3(aq) -> 3Ca(OH)2(aq) + 2FeCl3(aq) -> 2Fe(OH)3(s) + 3CaCl2(aq) NaOH(aq) + HCl(aq) -> NaOH(aq) + HCl(aq) -> H2O(l) + NaCl(aq) ...
Problem Set: Empirical and Molecular Formulas
... a) If 4.5 mol of TiCl4 react with 3.5 mol O2, identify both the limiting and excess reactants. b) How many moles of excess reactant will remain if the reaction goes to completion? ...
... a) If 4.5 mol of TiCl4 react with 3.5 mol O2, identify both the limiting and excess reactants. b) How many moles of excess reactant will remain if the reaction goes to completion? ...
1 - UCSB C.L.A.S.
... surroundings? (cwater = 4.18 J/ºC g) 4. Consider the reaction: CaCl2(s) → Ca2+(aq) + 2Cl-(aq) ΔH = -81.5 kJ If 20.0 g of calcium chloride are dissolved in 150 mL of water at 25.0 C, what will be the final temperature of the solution assuming no heat loss to the surroundings? 5. Define the following ...
... surroundings? (cwater = 4.18 J/ºC g) 4. Consider the reaction: CaCl2(s) → Ca2+(aq) + 2Cl-(aq) ΔH = -81.5 kJ If 20.0 g of calcium chloride are dissolved in 150 mL of water at 25.0 C, what will be the final temperature of the solution assuming no heat loss to the surroundings? 5. Define the following ...
File
... 39. An atom of nitrogen-13 decays by emitting a positron. The nucleus produced contains which of the following? A) 6 protons and 7 neutrons B) 7 protons and 6 neutrons C) 8 protons and 5 neutrons D) 7 protons and 7 neutrons E) 6 protons and 8 neutrons 40. Which of the following statements about atom ...
... 39. An atom of nitrogen-13 decays by emitting a positron. The nucleus produced contains which of the following? A) 6 protons and 7 neutrons B) 7 protons and 6 neutrons C) 8 protons and 5 neutrons D) 7 protons and 7 neutrons E) 6 protons and 8 neutrons 40. Which of the following statements about atom ...
Powerpoints - Holy Cross Collegiate
... of reactants and/or products involved in a chemical reaction. • However, the coefficient ratio can only be used to compare amounts of chemicals. • For example, in the formation of carbon dioxide gas, C(s) + O2(g) → CO2(g) it would be correct to say that 1 mol of carbon reacts with 1 mol of oxygen, b ...
... of reactants and/or products involved in a chemical reaction. • However, the coefficient ratio can only be used to compare amounts of chemicals. • For example, in the formation of carbon dioxide gas, C(s) + O2(g) → CO2(g) it would be correct to say that 1 mol of carbon reacts with 1 mol of oxygen, b ...
Chapter 14…Kinetic Theory
... (Ionic/molecular) compounds cause greater change of boiling/freezing points in solutions. Aluminum chloride (AlCl3) will dissociate into _____(how many) ions and will cause a (greater/smaller) ...
... (Ionic/molecular) compounds cause greater change of boiling/freezing points in solutions. Aluminum chloride (AlCl3) will dissociate into _____(how many) ions and will cause a (greater/smaller) ...
Chemical reaction
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive elements where both electronic and nuclear changes may occur.The substance (or substances) initially involved in a chemical reaction are called reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more products, which usually have properties different from the reactants. Reactions often consist of a sequence of individual sub-steps, the so-called elementary reactions, and the information on the precise course of action is part of the reaction mechanism. Chemical reactions are described with chemical equations, which symbolically present the starting materials, end products, and sometimes intermediate products and reaction conditions.Chemical reactions happen at a characteristic reaction rate at a given temperature and chemical concentration. Typically, reaction rates increase with increasing temperature because there is more thermal energy available to reach the activation energy necessary for breaking bonds between atoms.Reactions may proceed in the forward or reverse direction until they go to completion or reach equilibrium. Reactions that proceed in the forward direction to approach equilibrium are often described as spontaneous, requiring no input of free energy to go forward. Non-spontaneous reactions require input of free energy to go forward (examples include charging a battery by applying an external electrical power source, or photosynthesis driven by absorption of electromagnetic radiation in the form of sunlight).Different chemical reactions are used in combinations during chemical synthesis in order to obtain a desired product. In biochemistry, a consecutive series of chemical reactions (where the product of one reaction is the reactant of the next reaction) form metabolic pathways. These reactions are often catalyzed by protein enzymes. Enzymes increase the rates of biochemical reactions, so that metabolic syntheses and decompositions impossible under ordinary conditions can occur at the temperatures and concentrations present within a cell.The general concept of a chemical reaction has been extended to reactions between entities smaller than atoms, including nuclear reactions, radioactive decays, and reactions between elementary particles as described by quantum field theory.