Chemistry

A chemist wants to calculate the amount of heat that is absorbed by a sample of copper as it is melted. Which constant should she use? mc008-1.jpgHfus -mc008-2.jpgHvap mc008-3.jpgHvap -mc008-4.jpgHfus

a

Butane (C4 H10(g), mc031-1.jpgHf = -125.6 kJ/mol) reacts with oxygen to produce carbon dioxide (CO2 , mc031-2.jpgHf = -393.5 kJ/mol ) and water (H2 O, mc031-3.jpgHf = -241.82 kJ/mol) according to the equation below. mc031-4.jpg What is the enthalpy of combustion (per mole) of C4H10 (g)? Use mc031-5.jpg. -2,657.5 kJ/mol -5315.0 kJ/mol -509.7 kJ/mol -254.8 kJ/mol

a

Consider the following enthalpy diagram and enthalpies of intermediate and overall chemical reactions. mc025-1.jpg Which of the following statements is true? The overall chemical reaction is exothermic. There are two intermediate reactions in this system. The third intermediate reaction is endothermic. The longest arrow represents the overall chemical reaction.

a

Consider the following intermediate chemical equations. mc001-1.jpg Which overall chemical equation is obtained by combining these intermediate equations? mc001-2.jpg mc001-3.jpg mc001-4.jpg mc001-5.jpg

a

Consider the following intermediate chemical equations. mc029-1.jpg In the final chemical equation, HF and Omc029-2.jpg are the products that are formed through the reaction between mc029-3.jpg and Fmc029-4.jpg. Before you can add these intermediate chemical equations, you need to alter them by multiplying the second equation by 2 and reversing the first equation. first equation by 2 and reversing it. first equation by (1/2) and reversing the second equation. second equation by 2 and reversing it.

a

Consider the following intermediate chemical equations. mc032-1.jpg What is the enthalpy of the overall chemical reaction mc032-2.jpg? -205.7 kJ -113.4 kJ -14.3 kJ 78.0 kJ

a

Consider the following intermediate reactions. mc019-1.jpg The overall chemical reaction is as follows. mc019-2.jpg What is the correct enthalpy diagram using the Hess law for this system?

a

Consider the following intermediate reactions. mc019-1.jpg The overall chemical reaction is as follows. mc019-2.jpg What is the correct enthalpy diagram using the Hess law for this system? mc019-3.jpg mc019-4.jpg mc019-5.jpg mc019-6.jpg

a

Consider the intermediate chemical reactions. mc017-1.jpg The final overall chemical equation is mc017-2.jpg. When the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed. is halved. has its sign changed. is unchanged.

a

Consider the reaction 2AI(OH)3 + 3H2SO4 mc006-1.jpg X + 6Y. What are X and Y? X = AI2(SO4)3; Y = H2O X = AI2(SO4)3; Y = H2 X = AI2(SO3)3; Y = H2O X = AI2(SO3)3; Y = H2

a

Consider the total ionic equation below. mc022-1.jpg Which is the net ionic equation for the reaction?

a

Consider the total ionic equation below. mc022-1.jpg Which is the net ionic equation for the reaction? mc022-2.jpg mc022-3.jpg mc022-4.jpg mc022-5.jpg

a

Given that mc024-1.jpgG for the reaction below is -957.9 kJ, what is mc024-2.jpgGf of H2O? 4NH3(g) + 5O2(g) mc024-3.jpg 4NO(g) + 6H2O(g) mc024-4.jpgGf,NH3 = -16.66 kJ/mol mc024-5.jpgGf,NO = 86.71 kJ/mol -228.6 kJ/mol -206.4 kJ/mol 46.7 kJ/mol 90.7 kJ/mol

a

Hydrogen reacts with chlorine to form hydrogen chloride (HCl (g), mc012-1.jpgHf = -92.3 kJ/mol) according to the reaction below. mc012-2.jpg Which statement is correct? Use mc012-3.jpg. The enthalpy of the reaction is -184.6 kJ, and the reaction is exothermic. The enthalpy of the reaction is -184.6 kJ, and the reaction is endothermic. The enthalpy of the reaction is 184.6 kJ, and the reaction is endothermic. The enthalpy of the reaction is 184.6 kJ, and the reaction is exothermic.

a

Manganese dioxide (MnO2(s), mc008-1.jpgHf = -520.0 kJ) reacts with aluminum to form aluminum oxide (AI2O3(s), mc008-2.jpgHf = -1699.8 kJ/mol) and manganese according to the equation below. mc008-3.jpg What is the enthalpy of the reaction? Use mc008-4.jpg. -1,839.6 kJ -1,179.8 kJ 1,179.8 kJ 1,839.6 kJ

a

Marcela dissolves 80.0 g of ammonium nitrate in 50.0 mL of water at room temperature and notes that the temperature of the solution decreases by 5.0°C. Which correctly designates the signs of mc015-1.jpgH, mc015-2.jpgS, and mc015-3.jpgG for this reaction? mc015-4.jpgH > 0, mc015-5.jpgS > 0, and mc015-6.jpgG < 0 mc015-7.jpgH < 0, mc015-8.jpgS > 0, and mc015-9.jpgG < 0 mc015-10.jpgH > 0, mc015-11.jpgS > 0, and mc015-12.jpgG > 0 mc015-13.jpgH < 0, mc015-14.jpgS < 0, and mc015-15.jpgG > 0

a

The reaction below proceeds spontaneously at 298 K. NH3(g) +Cl2(g)mc013-1.jpgNH4Cl(s) What is the sign of the entropy change, mc013-2.jpgS? mc013-3.jpgS is negative because the product is less random than the reactants. mc013-4.jpgS is negative because the reactants are less random than the product. mc013-5.jpgS is positive because the product is less random than the reactants. mc013-6.jpgS is positive because the reactants are less random than the product.

a

Use the following table to answer the question. Strong acids Weak acids Weak bases Strong bases HBr CH3COOH NH3 NaOH HNO3 HF NH4OH KOH H2SO4 HCN Ca(OH)2 Which of these is a neutral salt? Na2SO4 NaCN KF (NH4)2SO4

a

What is mc025-1.jpgGrxn for the equation below? NaOH(aq) + HCl(aq) mc025-2.jpg H2O(l) + NaCl(aq) mc025-3.jpgHrxn = -56.13 kJ mc025-4.jpgSrxn = 87.1 J/K T = 303 K Use mc025-5.jpgG = mc025-6.jpgH - Tmc025-7.jpgS. -82.5 kJ -29.7 kJ 26,500 kJ 27,000 kJ

a

What is the final chemical equation from the following intermediate chemical equations? mc009-1.jpg mc009-2.jpg mc009-3.jpg mc009-4.jpg mc009-5.jpg

a

Which equation represents the correct net ionic equation for the reaction between Ca(OH)2 and H2SO4?

a

Which graph represents an exothermic reaction?

a

Which statement describes spontaneous processes? proceed without continuous external influence and have an overall negative free energy change proceed without continuous external influence and have an overall positive free energy change proceed with continuous external influence and have an overall negative free energy change proceed with continuous external influence and have an overall positive free energy change

a

A base is added to an acid during a titration. A pH meter is used to monitor the reaction's progress. When should the addition of base stop? when adding a few drops of base causes a large decrease in pH when adding a few drops of base causes a large increase in pH when adding a few milliliters of base causes a large increase in pH when adding a few milliliters of base causes a large decrease in pH

b

An acid (X) reacts with a base (Y) to produce Mg3(PO4)2. What are X and Y?

b

An engineer wants to determine an efficient method for condensing large amounts of steam into liquid water. Which constant should she use? mc009-1.jpgHfus -mc009-2.jpgHvap mc009-3.jpgHvap -mc009-4.jpgHfus

b

Butane C4 H10 (g),(mc016-1.jpgHf = -125.7), combusts in the presence of oxygen to form CO2 (g) (mc016-2.jpgHf = -393.5 kJ/mol), and H2 O(g) (mc016-3.jpgHf = -241.82) in the reaction: mc016-4.jpg What is the enthalpy of combustion, per mole, of butane? Use mc016-5.jpg. -5,314.8 kJ/mol -2,657.4 kJ/mol 2,657.4 kJ/mol 5,314.8 kJ/mol

b

Consider the following intermediate chemical equations. mc006-1.jpg In the final chemical equation, NaCl and Omc006-2.jpg are the products that are formed through the reaction between mc006-3.jpg and Clmc006-4.jpg. Before you can add these intermediate chemical equations, you need to alter them by multiplying the second equation by 2. multiplying the first equation by 2. multiplying the first equation by (1/2). multiplying the second equation by (1/4).

b

Consider the following intermediate chemical equations. mc014-1.jpg What is the enthalpy of the overall chemical reaction mc014-2.jpg? -4,580 kJ -1,300 kJ 1,300 kJ 4,580 kJ

b

Consider the following intermediate chemical equations. mc015-1.jpg What is the enthalpy of the overall chemical equation NO(g) + O(g) mc015-2.jpg NOmc015-3.jpg(g)? -305 kJ -304.1 kJ -93.7 kJ 588.7 kJ

b

Ethyne (C2 H2 (g), mc032-1.jpgHf = 226.77 kJ/mol) undergoes complete combustion in the presence of oxygen to produce carbon dioxide (CO2 (g), mc032-2.jpgHf = -393.5 kJ/mol ) and water (H2 O(g), mc032-3.jpgHf = -241.82 kJ/mol) according to the equation below. mc032-4.jpg What is the enthalpy of combustion (per mole) of C2 H2 (g)? Use mc032-5.jpg. -2511.2 kJ/mol -1255.6 kJ/mol -862.1 kJ/mol -431.0 kJ/mol

b

How should the enthalpy of an intermediate step be manipulated when used to produce an overall chemical equation? Multiply the enthalpy by 1 if the chemical equation is reversed. Multiply the enthalpy by -1 if the chemical equation is reversed. Add 2 to the enthalpy if the coefficients must be doubled. Add 2 to the enthalpy if the coefficients must be cut in half.

b

Jason combines the two intermediate steps shown. mc027-1.jpg Which best describes what Jason should do with the oxygen molecules? Place two of them as products. Place two of them as reactants. Cancel them out because there is one in each equation. Double them because there is one in each equation.

b

Sulfur reacts with oxygen to form sulfur dioxide (SO2(g), mc010-1.jpgHf = -296.8 kJ/mol) according to the equation below. mc010-2.jpg What is the enthalpy change for the reaction? Use mc010-3.jpg. -593.6 kJ -296.8 kJ 296.8 kJ 593.6 kJ

b

The graph below illustrates a change in energy during a phase change. mc003-1.jpg Which explanation correctly describes the phase change in the graph? This is an exothermic reaction that involves melting. This is an exothermic reaction that involves freezing. This is an endothermic reaction that involves vaporization. This is an endothermic reaction that involves condensation.

b

The mc002-1.jpgHrxn of formation of carbon dioxide is negative. Which statement is true?

b

The mc002-1.jpgHrxn of formation of carbon dioxide is negative. Which statement is true? The reaction is endothermic. The reaction is exothermic. The amount of carbon dioxide is more than the amount of reactants. The amount of carbon dioxide is less than the amount of reactants.

b

The molar heat of vaporization for methane, CH4, is 8.53 kJ/mol. How much energy is absorbed when 54.8 g of methane vaporizes at its boiling point? Use mc031-1.jpg. 6.42 kJ 29.1 kJ 137 kJ 467 kJ

b

This table has information about the heat of fusion and the heat of vaporization of different substances. mc024-1.jpg Which substance absorbs 58.16 kJ of energy when 3.11 mol vaporizes? Use mc024-2.jpg. CH4 H2S CO2 NaCl

b

Trevor dissolves sodium hydroxide pellets in a beaker of water at room temperature, and notes that the beaker becomes warm. Which correctly designates the signs of mc030-1.jpgH, mc030-2.jpgS, and mc030-3.jpgG for this process? mc030-4.jpgH > 0, mc030-5.jpgS > 0, and mc030-6.jpgG < 0 mc030-7.jpgH < 0, mc030-8.jpgS > 0, and mc030-9.jpgG < 0 mc030-10.jpgH > 0, mc030-11.jpgS > 0, and mc030-12.jpgG > 0 mc030-13.jpgH < 0, mc030-14.jpgS < 0, and mc030-15.jpgG > 0

b

What is enthalpy? the total concentration of the system the total heat content of the system the total pressure of the system the total internal energy of the system

b

What is the net ionic equation for the reaction that is represented by the following total ionic equation? mc024-1.jpg mc024-2.jpg mc024-3.jpg mc024-4.jpg mc024-5.jpg

b

What scientific tool would be the most helpful when measuring the temperature of a substance that is undergoing a phase change? a spectrophotometer a thermometer the periodic table a scale

b

Which compound will conduct electricity when it is dissolved in water?

b

Which energy changes are associated with a liquid boiling? Energy is released, and potential energy decreases. Energy is absorbed, and potential energy increases. Energy is released, and kinetic energy decreases. Energy is absorbed, and kinetic energy increases.

b

Which process involves a decrease in entropy? burning natural gas water freezing into ice water evaporating on heating dry ice subliming

b

Which process involves an increase in entropy? crystallization of a solute from a solution ice melting into liquid water iodine vapor forming solid iodine condensing a gas into a liquid

b

Which salt is produced when H2SO4 reacts with NaOH?

b

Which salt is produced when H2SO4 reacts with NaOH? K2SO3 Na2SO4 Na2SO3 K2SO4

b

Which statement about mc028-1.jpgHf is true?

b

Which statement about mc028-1.jpgHf is true? It is zero for any compound in its standard state. It is positive when the bonds of the product store more energy than those of the reactants. It is negative when a compound forms from elements in their standard states. It is zero for any element that is in the liquid state.

b

A sample of substance X that has a mass of 326.0 g releases 4325.8 cal when it freezes at its freezing point. If substance X has a molar mass of 58.45 g/mol, what is the molar heat of fusion for substance X? Use mc019-1.jpg. 13.31 cal/mol 74.00 cal/mol 775.6 cal/mol 19054.7 cal/mol

c

Consider the following intermediate chemical equations. mc008-1.jpg When you combine the intermediate chemical equations, which substance do you cancel out? P Clmc008-2.jpg mc008-3.jpg PClmc008-4.jpg

c

Consider the reaction 2SO2(g) + O2(g) mc021-1.jpg 2SO3(g). Substance mc021-2.jpgHf (kJ/mol) S (J/(molmc021-3.jpgK)) SO3(g) -396 130.58 SO2(g) -297 191.50 O2(g) 0 205.00 What is the mc021-4.jpgGrxn of this reaction, and would it be spontaneous or nonspontaneous at 300.0 K? Use mc021-5.jpgG = mc021-6.jpgH - Tmc021-7.jpgS. -296 kJ/mol, spontaneous -296 kJ/mol, nonspontaneous -100 kJ/mol, spontaneous -100 kJ/mol, nonspontaneous

c

Consider the reaction. mc026-1.jpg Standard Enthalpies of Formation Substance DHf (kJ/mol) C2 H2 (g) 226.73 CaCO3 (s) -1206.92 CaO (s) -635.09 CO (g) -110.525 CO2 (g) -393.509 H 2 O (I) -285.8 H 2 O (g) -241.818 C (s), diamond 1.895 C (s), graphite 0.0 Based on the equation and the information in the table, what is the enthalpy of the reaction? Use mc026-2.jpg. -453.46 kJ -226.73 kJ 226.73 kJ 453.46 kJ

c

Consider the total ionic equation below. mc029-1.jpg What are the spectator ions in this equation? H+ and OH- H+ and mc029-2.jpg mc029-3.jpg and mc029-4.jpg mc029-5.jpg and OH-

c

Copper has a mc033-1.jpgHfus = 13.0 kJ/mol. What mass of copper releases 112.4 kJ of heat as it freezes? Use mc033-2.jpg. 9.42 g 6.75 g 549 g 1590 g

c

Look at the diagram below. mc003-1.jpg Which best describes what is taking place in the diagram? The calibration of an acid is being completed with a base. A direct measurement of pH is taking place. An indirect measurement of pH is taking place. The final volume of an acid or base is being measured.

c

The enthalpies of formation of the compounds in the combustion of methane, mc019-1.jpg, are CH4 (g): mc019-2.jpgHf = -74.6 kJ/mol; CO2 (g): mc019-3.jpgHf = -393.5 kJ/mol; and H2 O(g): mc019-4.jpgHf = -241.82 kJ/mol. How much heat is released by the combustion of 2 mol of methane? Use mc019-5.jpg. mc019-6.jpg80.3 kJ mc019-7.jpg802.5 kJ mc019-8.jpg1,605.1 kJ mc019-9.jpg6,420.3 kJ

c

The enthalpy of formation for C6 H6 (I) is 49.0 kJ/mol. Consider the following reaction. mc014-1.jpg Is the reaction endothermic or exothermic, and what is the enthalpy of reaction? Use mc014-2.jpg. exothermic; mc014-3.jpgHrxn = 49.0 kJ exothermic; mc014-4.jpgHrxn = -49.0 kJ endothermic; mc014-5.jpgHrxn = 49.0 kJ endothermic; mc014-6.jpgHrxn = -49.0 kJ

c

The equation CaCO3(s) mc019-1.jpg CaO(s) + CO2(g) shows the decomposition of calcium carbonate. mc019-2.jpgH = 178.3 kJ/mol, and mc019-3.jpgS = 160.5 J/(molmc019-4.jpgK). The free energy change for the reaction is 130.5 kJ/mol. Which correctly states the temperature at which the reaction took place and whether the reaction is spontaneous or nonspontaneous? Use mc019-5.jpgG = mc019-6.jpgH - Tmc019-7.jpgS. 0.30 K, spontaneous 1.92 K, spontaneous 297.8 K, nonspontaneous 1,924 K, nonspontaneous

c

This is the equation for the dissociation of ammonia gas at 293 K. mc017-1.jpgH = 145 kJ and mc017-2.jpgS = 195 J/k. 2NH3(g) mc017-3.jpg N2(g) + 3H2(g) Which correctly states the mc017-4.jpgG for this dissociation and whether the process is spontaneous or nonspontaneous? Use mc017-5.jpgG = mc017-6.jpgH - Tmc017-7.jpgS. -87.87 kJ, spontaneous -50 kJ, spontaneous 87.9 kJ, nonspontaneous 202.14 kJ, nonspontaneous

c

When two intermediate chemical equations are combined, the same substance that appears in the same phase can be canceled out, provided that it is a reactant in one intermediate reaction and a catalyst in the other reaction. it is a product in one intermediate reaction and a catalyst in the other reaction. it is a reactant in one intermediate reaction and a product in the other reaction. it is a reactant in both of the intermediate reactions.

c

Which equation represents the total ionic equation for the reaction of HNO3 and NaOH? mc017-1.jpg mc017-2.jpg mc017-3.jpg mc017-4.jpg

c

Which is the correctly balanced chemical equation for the reaction of KOH and H2SO4?

c

Which is the correctly balanced chemical equation for the reaction of KOH and H2SO4? mc015-1.jpg mc015-2.jpg mc015-3.jpg mc015-4.jpg

c

Which process or processes produce an increase in entropy? i. N2(g) + 3H2(g) mc008-1.jpg NH3(g) ii. C10H8(g) mc008-2.jpg C10H8(s) iii. CH3OH(l) mc008-3.jpg CH3OH(aq) i only ii and iii iii only i and iii

c

Which scientific tool is the most useful when trying to convert a known amount of grams of water to moles of water? a scale a thermometer the periodic table a spectrophotometer

c

Which statement describes a system that consists of sugar crystals dissolving in water? The system becomes more ordered and has an increase in entropy. The system becomes more ordered and has a decrease in entropy. The system becomes more disordered and has an increase in entropy. The system becomes more disordered and has a decrease in entropy.

c

he enthalpies of formation of the compounds in the combustion of methane, mc019-1.jpg, are CH4 (g): mc019-2.jpgHf = -74.6 kJ/mol; CO2 (g): mc019-3.jpgHf = -393.5 kJ/mol; and H2 O(g): mc019-4.jpgHf = -241.82 kJ/mol. How much heat is released by the combustion of 2 mol of methane? Use mc019-5.jpg. mc019-6.jpg80.3 kJ mc019-7.jpg802.5 kJ mc019-8.jpg1,605.1 kJ mc019-9.jpg6,420.3 kJ

c

Consider the incomplete reaction below. NaOH + X mc005-1.jpg NaCH3COO + H2O What is X in this reaction?

d

Consider the total ionic equation below. mc018-1.jpg What are the spectator ions in this equation?

d

Consider the total ionic equation below. mc018-1.jpg What are the spectator ions in this equation? H+ and OH- H+ and Ba2+ mc018-2.jpg and mc018-3.jpg mc018-4.jpg and mc018-5.jpg

d

During an endothermic phase change, what happens to the potential energy and the kinetic energy? Potential energy stays the same, and kinetic energy increases. Potential energy increases, and kinetic energy increases. Potential energy decreases, and kinetic energy decreases. Potential energy increases, and kinetic energy stays the same.

d

How is enthalpy used to predict whether a reaction is endothermic or exothermic? When the enthalpy of the reactants is higher than the enthalpy of the products, the reaction is endothermic. When the enthalpy of the products is higher than the enthalpy of the reactants, the reaction is exothermic. When the enthalpy change of the reaction is positive, the reaction is exothermic. When the enthalpy change of the reaction is positive, the reaction is endothermic.

d

NaCl has a mc020-1.jpgHfus = 30.2 kJ/mol. What is the mass of a sample of NaCl that needs 732.6 kJ of heat to melt completely? Use mc020-2.jpg. 24.3 g 82.7 g 1,407.1 g 1,417.7 g

d

The molar heat of fusion for water is 6.01 kJ/mol. How much energy must be added to a 75.0-g block of ice at 0°C to change it to 75.0 g of liquid water at 0°C? Use mc012-1.jpg. 1.44 kJ 10.18 kJ 12.48 kJ 25.04 kJ

d

Use the following table to answer the question. Strong acids Weak acids Weak bases Strong bases HBr CH3COOH NH3 NaOH HCl HF NH4OH KOH H2SO4 HCN Cu(OH)2 Ca(OH)2 Which of these salts has the highest pH? K2SO4 Cu2SO4 NH4Cl NaCH3COO

d

What is mc009-1.jpgS for the reaction N2(g) +O2(g) mc009-2.jpg 2NO? Use mc009-3.jpgG = 173.3 kJ at 303.0 K and mc009-4.jpgH = 180.7 kJ. Use mc009-5.jpgG = mc009-6.jpgH - Tmc009-7.jpgS. 7.4 J/K 7.4 kJ/K 24.42 kJ/K 24.42 J/K

d

Which are produced when HCl reacts with Ca(OH)2? Cl2, H3, and CaO CaCl and H3O CaO, Cl2, and H2O CaCl2 and H2O

d

Which term is used to describe the amount of heat that is required to convert 1 mol of a liquid to a gas? dew point boiling point molar heat of fusion molar heat of vaporization

d

Which is the first step in the titration process? Clean and rinse the burette with water. Read and record the initial burette volume. Fill the burette with standardized base solution. Rinse the burette with standardized base solution.

a

Which of the glassware shown below is an Erlenmeyer flask?

a

Which statement is true for most chemical reactions? An energy change occurs during the breaking and forming of bonds. The internal energy of the system increases during a reaction. Energy is released during the formation of reactants. The enthalpy of the products is higher than the enthalpy of the reactants.

a

Which statement is true if the mc001-1.jpgHrxn of a reaction is positive? The reaction is endothermic. The reaction is exothermic. There is more reactant than product. There is more product than reactant.

a

Which step accurately describes how to measure the final burette volume? Locate the bottom of the meniscus and record volume to the nearest 0.01 mL. Locate the bottom of the meniscus and record volume to the nearest 0.1 mL. Locate the top of the meniscus and record volume to the nearest 0.01 mL. Locate the top of the meniscus and record volume to the nearest 0.1 mL.

a

Ammonia (NH3 (g), mc009-1.jpgHf = -45.9 kJ/mol ) reacts with oxygen to produce nitrogen and water (H2 O(g), mc009-2.jpgHf = -241.8 kJ/mol) according to the equation below. mc009-3.jpg What is the enthalpy of the reaction? Use mc009-4.jpg.

b

Consider the following enthalpy diagram. mc024-1.jpg What is the overall enthalpy change DHrxn for the system? -1,300 kJ -300 kJ 300 kJ 1,300 kJ

c

Which instrument is most often used to measure acid volume before a titration begins? a burette a beaker a volumetric pipette an Erlenmeyer flask

c

Which of these is the main goal of any titration? to observe the effect of indicators on acids to observe the effect of indicators on bases to determine the concentration of one of the reactants to determine the effects of a base on one of the products

c

Consider the graph below. mc005-1.jpg Which phase change is most likely taking place in this graph? a gas to a liquid a liquid to a solid a gas to a solid a solid to a liquid

d

Maya, a student, performs a titration. She completes the following steps as part of her titration procedure. 1. She cleans and rinses a burette with base solution. 2. She fills the burette with standardized base solution. 3. She adds a base from a burette to an acid. 4. She observes a color change in the Erlenmeyer flask. 5. She continues to add more base. Based on the above procedure, will she obtain accurate results? Yes, because the more base there is, the better the results will be. No, because she initially contaminated the burette with base. Yes, because she used a standardized base solution in the burette. No, because she did not stop adding base once the color changed.

d

When are drops of indicator most likely added to the Erlenmeyer flask? when preparing the burette when filling the pipette with acid when recording the initial burette volume when preparing to measure pH change

d

Which of the following is the main reason to use titration in chemistry? to write a balanced chemical equation for a reaction to calculate the number of moles of an acid or base to use stoichiometric ratios for converting moles to find the molarity of an unknown acid or base

d