| Assessment Questions: 31 results |
Solutions : FreezePtDepression (20 Variations)
It takes 6.86 kg of ethylene glycol (antifreeze) to decrease the freezing point of 6.50 kg of water to -25.0oF (-31.7oC). How much sodium chloride (NaCl) would it take to decrease the freezing point of 6.50 kg of water to -25.0oF? (Assuming all the salt will dissolve in that amount of water.)
Solutions / Solvents
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Solutions : GeneralSolutions (10 Variations)
You have 500.0mL of 0.100M aqueous MgBr2. Which of the following statements are true?
Solutions / Solvents
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Solutions : SolnPrepProcedure (10 Variations)
You want to prepare 250mL of a 0.0150M solution of KCl. Which of the following procedures would give you the best results?
Solutions / Solvents
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Solutions : SolutionNanoPics (4 Variations)
The drawings below represent flasks of aqueous solutions. Each pink dot represents a dissolved solute particle.
Which of the following solutions is most concentrated?
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500 mL
Solution A
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500 mL
Solution B
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500 mL
Solution C
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250 mL
Solution D
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250 mL
Solution E
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250 mL
Solution F
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Solutions / Solvents
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Solutions : IonConcentration (4 Variations)
Which of the following solutions has the greatest concentration of Na+ ions?
Solutions / Solvents |
Chemometrics
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Solutions : MassSoluteInSoln (10 Variations)
What is the mass of the solute in 500mL of 0.341M ammonium chloride?
Solutions / Solvents |
Chemometrics
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Solutions : RelativeConc (4 Variations)
What are the relative concentrations of the ions in 0.10 M aqueous sulfuric acid?
Solutions / Solvents |
Stoichiometry
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Solutions : ReverseOsmosis (20 Variations)
You are given a water sample that contains ammonium chloride (NH4Cl). You determine the concentration of the salt to be 0.500 M and decide to purify the water using reverse osmosis. What is the minimum pressure that must be applied at 30.0oC to force the water through the membrane?
Solutions / Solvents |
Transport Properties
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Solutions : SolnConcAfterMixing (4 Variations)
10 mL of 0.1 M BaCl2(aq) is mixed with 10 mL of 0.1 M AgNO3(aq). What are the concentrations of the ions in the final mixture?
Solutions / Solvents |
Chemometrics
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Solutions : SolnPrepByDilution (10 Variations)
For the analysis of trace metals it is necessary to prepare solutions of very low concentrations from a stock solution of higher concentration using a micropipet and a volumetric flask. What volume of a 0.0010 M solution of Zn(NO3)2 (aq) would be required to prepare a 5.0 nM solution of Zn2+ in a 250mL flask?
Solutions / Solvents |
Chemometrics
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Solutions : SolnPrepByMass (4 Variations)
You are required to prepare 5 L of a solution containing 1.000 x 10-3 mol/L of Cu2+(aq). Which of the following procedures would produce an appropriate solution?
Solutions / Solvents |
Chemometrics
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Solutions : ConvertConcUnits (10 Variations)
The maximum concentration of arsenic in drinking water that is allowed by the EPA is 0.050 mg/L. Express this as a weight percent. (You can assume the density of the water solution is 1.0g/mL.)
Solutions / Solvents |
Nomenclature / Units / Symbols |
Chemometrics
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Solutions : GramsToMolalSoln (20 Variations)
How many grams of citric acid need to be added to 750 ml of ethanol to make a 0.50 m solution?
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Density (g/ml)
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Molecular Weight (g/mol)
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Citric acid
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1.665
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192.14
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Ethanol
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0.7893
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46.07
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Solutions / Solvents |
Nomenclature / Units / Symbols |
Chemometrics
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Solutions : MixturesMolcPics (11 Variations)
Which of the following combinations of substances corresponds to the molecular scale diagram shown below?
Solutions / Solvents |
Noncovalent Interactions |
Precipitation / Solubility
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Solutions : WtPercentToMolarity (4 Variations)
A common concentration unit used commercially is percent weight per volume (%W/V) which is the number of grams of solute in 100 mL of solution. A bottle of vinegar contains 5 %W/V acetic acid (CH3COOH). What is the molar concentration of acetic acid in the vinegar?
Solutions / Solvents |
Nomenclature / Units / Symbols |
Chemometrics
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Solutions : CalcMolarityFromPPT (10 Variations)
You are given a water sample to analyze from a lake contaminated with lead. It takes 24 mL of 0.020 M NaCl to exactly precipitate the Pb2+ ions from 61 mL of the water sample. What is the concentration of Pb2+ ions in the water?
Pb2+(aq) + 2NaCl(aq) PbCl2(s) + 2Na+(aq)
Solutions / Solvents |
Nomenclature / Units / Symbols |
Chemometrics
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Electrochemistry : CalcDeltaGfromE (20 Variations)
The following electrochemical data may be helpful in answering the question below. 
Calculate the  Go for the oxidation of 2 mole of silver in the following balanced reaction. 2Ag(s) + CaI2(aq)  Ca(s) + 2AgI(s)
Electrochemistry |
Oxidation / Reduction
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Electrochemistry : CalcStandRedPotential (20 Variations)
The following electrochemical data may be helpful in answering the question below.
Calculate Eo for the following balanced reaction. Fe(s) + Fe2(SO3)3(s) 3FeSO3(s)
Electrochemistry |
Oxidation / Reduction
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Electrochemistry : GeneralCorrosion (10 Variations)
Which of the following statements not is true?
Electrochemistry |
Oxidation / Reduction
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Electrochemistry : GeneralElectrochem (20 Variations)
Which of the following statements is not correct?
Electrochemistry |
Oxidation / Reduction
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Electrochemistry : SacrificialAnode (10 Variations)
The following electrochemical data may be helpful in answering the question below.
One method for protecting metals against corrosion is to connect the metal directly to a "sacrificial anode". This is the method used to protect pipelines and ships hulls. Which of the following metals would you consider the best candidate for a sacrificial anode for a ship's hull? The hull is steel (which is mostly iron).
Electrochemistry |
Oxidation / Reduction |
Metals
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Electrochemistry : CalcInterpretEo (20 Variations)
The following electrochemical data may be helpful in answering the question below.
Consider a cell composed of the following half-reactions. Determine the
magnitude of E° for the cell and decide whether the reaction will be
product-favored or reactant-favored as written.
Cr(s) Cr3+(aq) + 3e-
Ce4+(aq) + e- Ce3+(aq)
Electrochemistry |
Oxidation / Reduction
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Electrochemistry : IDHalfRxns (20 Variations)
What are the half-reactions for the reaction of Cs and Cl2 in the formation of CsCl2?Cs + Cl2 CsCl2
Electrochemistry |
Oxidation / Reduction
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Electrochemistry : IDRedOxAgents (20 Variations)
In the following balanced reaction, identify the oxidizing and reducing agents.Fe + Fe2(SO3)3 3FeSO3
Electrochemistry |
Oxidation / Reduction
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Electrochemistry : ElectrolysisHalfRxns (20 Variations)
The following electrochemical data may be helpful in answering the question below.
What will be the products of the electrolysis of an aqueous solution of Tin (II) sulfate (SnSO4)? (The electrodes themselves are platinum.)
Electrochemistry |
Oxidation / Reduction |
Electrolytic / Galvanic Cells / Potentials
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Electrochemistry : BatteryHalfRxns (20 Variations)
The two half-reactions for the LeClanche dry cell battery are shown below. Identify the oxidizing and reducing agents in this cell. Zn(s) Zn2+(aq) + 2e-
2NH4+(aq) + 2e- 2NH3(g) + H2(g)
Electrochemistry |
Oxidation / Reduction |
Electrolytic / Galvanic Cells / Potentials
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Electrochemistry : ECellObservations (20 Variations)
Consider the electrochemical cell diagram shown below. As you observe the reaction in the cell, you notice that the tin electrode seems to be disappearing while there are deposits forming on the silver electrode. Which of the following is a correct statement?
Electrochemistry |
Oxidation / Reduction |
Electrolytic / Galvanic Cells / Potentials
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Electrochemistry : ElectrolysisCalcs (20 Variations)
Calculate the mass of gold that could be plated from a solution with a current of 0.40 A for 22 min. Au3+(aq) + 3 electrons Au(s)
Electrochemistry |
Oxidation / Reduction |
Electrolytic / Galvanic Cells / Potentials
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Electrochemistry : FuelCellsAndBatteries (20 Variations)
Determine whether the following descriptions are characteristic of fuel
cells, primary batteries, secondary batteries or both batteries and fuel
cells.
Electrochemistry |
Oxidation / Reduction |
Electrolytic / Galvanic Cells / Potentials
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Electrochemistry : BalanceRedoxRxn (20 Variations)
The following electrochemical data may be helpful in answering the question below.
Magnesium reacts with nitric acid to form magnesium nitrate and nitrogen monoxide in an acidic aqueous solution. Write the balanced equation for this reaction.
Electrochemistry |
Oxidation / Reduction |
Electrolytic / Galvanic Cells / Potentials
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Electrochemistry : BatteryDesign (8 Variations)
Students are attempting to construct a battery in the laboratory that will light up a light bulb. Compare the following lists prepared by students and determine which student will not be able to successfully build a "battery" that will light up the bulb.
Electrochemistry |
Oxidation / Reduction |
Electrolytic / Galvanic Cells / Potentials
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