77 Results
The Avogadro Constant   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Molar Mass   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Analysis of Compounds   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Limiting Reagent   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Equations and Mass Relationships   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Balancing Chemical Equations   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Amount of Substance   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Mole   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Exploding Soap Bubbles: Hydrogen + Oxygen   
(Movie/Animation, Audio/Visual (6))
Explosions of bubbles filled with only hydrogen and with varying ratios of hydrogen and oxygen are demonstrated.
Stoichiometry   
(Movie/Animation, Audio/Visual (4))
The Stoichiometry group contains three groups: Exploding Soap Bubbles: Hydrogen + Oxygen; Acid-Base Titrations and Animation; and Redox Titration and Animation.
Gas Stoichiometry   
(Movie/Animation, Audio/Visual (3))
Gas is generated from one mole of liquid of solid and the volume is measured using a gas collection system.
Combustion of Hexane   
(Movie/Animation, Audio/Visual (2))
Combustion of hexane with limited oxygen and addition of water to burning hexane are demonstrated.
Stoichiometry (Netorials)   
(Instructional Material (1))
Stoichiometry: this is a resource in the collection "Netorials". Stoichiometry shows how to balance chemical equations, deal with limiting reactants, computing yelds, working with molarity and different concentrations as well as the use of stoichiometry principles in the chemical analysis of a mixture. The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Thermodynamics, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.
Stoichiometry : SolnStoich (4 Variations)   
(Assessment Material (1))
You are working in a forensic lab and are given a blood sample from a suspected drunk driver and asked to determine the person's blood alcohol level. The legal limit is 0.08% by mass in most states. You use the following reaction in your determination, assuming only the ethanol (C2H5OH) in the blood sample will react with the dichromate.
16H+(aq) + 2Cr2O72-(aq) + C2H5OH(l)4Cr3+(aq) + 11H2(l) + 2CO2(g)

If 14.6 mL of 0.10 M K2Cr2O7 are needed to react completely with 28 g of blood, what is the blood alcohol level of the driver?

Stoichiometry : RxnTable (10 Variations)   
(Assessment Material (1))
Iron reacts with oxygen to form iron(III) oxide according to the following reaction.

4Fe(s) + 3O2(g)2Fe2O3(s)


Fe(s) O2(g) Fe2O3(s)
Initial Amount - - -
Change - - -
End Amount - - -

Complete the reaction table for a reaction mixture containing 12.0 moles of iron and 10.0 moles of oxygen, and select the true statement(s) from following list.

Stoichiometry : GivenMassCalcStMat (10 Variations)   
(Assessment Material (1))
Aspirin is a common analgesic. If you want to produce 250. mg of aspirin (C9H8O4) from the reaction of C7H6O3 and C4H6O3, what is the minimum amount of C7H6O3 that is needed?

2C7H6O3(s) + C4H6O3(l) 2C9H8O4(s) + H2O(l)

Stoichiometry : RxnMolsProduced (8 Variations)   
(Assessment Material (1))
Given the following balanced chemical reaction:
4A + 3B2 2A2B3
If 12 moles of A are reacted with excess B2, how many moles of A2B3 will be produced?
Very carefully enter the number below.
Stoichiometry : MolsO2ToReactFuel (10 Variations)   
(Assessment Material (1))
Butane can be used as a fuel. How many moles of oxygen are needed to completely react with 3.0 moles of butane?

The unbalanced reaction equation is given below:
C4H10(g) + O2(g) CO2(g) + H2O(g)

Stoichiometry : GivenYieldCalcStMat (4 Variations)   
(Assessment Material (1))
Calcium oxide and water are produced by heating calcium hydroxide. If the reaction has an expected yield of 60%, how much calcium hydroxide should be reacted to produce 115g of calcium oxide?

Ca(OH)2 CaO + H2O

Atoms,_Molecules_and_Ions : CalcMolarMass (8 Variations)   
(Assessment Material (1))
What is the molar mass of potassium phosphate, K3PO4?

Enter the numeric value very carefully below, rounding to one decimal place only. Do not put the units in, but think about what the units are!

Atoms,_Molecules_and_Ions : IonicFormula (10 Variations)   
(Assessment Material (1))
Which pair of ions will form a compound of formula M2X?
Atoms,_Molecules_and_Ions : BinaryMolcFromImage (8 Variations)   
(Assessment Material (1))
Which of the following binary compounds could the figure below best represent?

Atoms,_Molecules_and_Ions : AtomicRatio (10 Variations)   
(Assessment Material (1))
Which compound(s) contain the most nitrogen atoms per molecule or formula unit?
Bonding : DetermineStructure (8 Variations)   
(Assessment Material (1))
H A substance is analyzed and found to contain 57.10% carbon, 4.80% hydrogen and 38.06% oxygen by weight. Its molecular weight is determined to be 126.11 g/mol. Which of the structures shown are possible structures for the substance?
Stoichiometry : PrecipYield (3 Variations)   
(Assessment Material (1))
In a laboratory experiment to determine accurately the amount of barium in solution, aqueous sulfuric acid was added to the solution to precipitate barium sulfate, which was then filtered and weighed. In this experiment it is MOST important that ...
Stoichiometry : FormulaFromComp (8 Variations)   
(Assessment Material (1))
Lactic acid is the substance that makes your muscles burn when you've been exercising hard. Lactic acid is composed of 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by weight. If it has a molar mass of 90 g/mol, what is its molecular formula?
Stoichiometry : ExplainYldError (4 Variations)   
(Assessment Material (1))
Your TA gives you an aqueous solution containing an unknown quantity of AgNO3(aq) and an unknown quantity of Mg(NO3)2(aq). You are asked to determine the molarity of Ag+ in the solution. You add HCl(aq) to your unknown to precipitate the silver as AgCl(s), then filter out the precipitate, dry it, weigh it, and calculate the concentration of silver ion. However, your TA tells you that your calculated value of [Ag+(aq)] is lower than the actual value. Which of the following could account for your answer being too low? There may be more than one correct answer.
Stoichiometry : CombustionAnalysis (10 Variations)   
(Assessment Material (1))
While working in the lab, you find a bottle of white powder labeled "analgesic compound #5". Since the original investigator neglected to record the identity of the substance, you decide to perform a combustion analysis to identify the compound. You have a 65.7 g sample that when burned produces 182 g CO2 and 51.7 g H2O. What is the formula of this compound? (The compound only consists of C,H, and O.)
Stoichiometry : AtomsAndGrams (10 Variations)   
(Assessment Material (1))
How many moles of atoms does a 500. g bar of gold contain?
Solutions : RelativeConc (4 Variations)   
(Assessment Material (1))
What are the relative concentrations of the ions in 0.10 M aqueous sulfuric acid?
Stoichiometry : CalcPercentPurity (4 Variations)   
(Assessment Material (1))
To test the purity of calcium sulfate, you dissolve a 4.56g sample in water and add oxalic acid to precipitate out calcium oxalate. If 3.45g of precipitate forms, what is the percent purity of the calcium sulfate?

CaSO4(aq) + H2C2O4(aq) CaC2O4(s) + H2SO4(aq)

Stoichiometry : CalcWtPercent (6 Variations)   
(Assessment Material (1))
A standard dose of antacid as a calcium supplement is two tablets. The active ingredient in many of these tablets is calcium carbonate. One tablet, having a weight of 1.415 g, is reacted with excess HCl(aq) to produce 0.22 g CO2. What is the weight percent of calcium in this tablet?

CaCO3(s) + 2HCl(aq)CaCl2(aq) + H2O(l) + CO2(g)

Stoichiometry : TheorYieldDeviation (10 Variations)   
(Assessment Material (1))
You reacted a known amount of phosphorous triiodide with excess water and determined that the percent yield of phosphoric acid was less than 100%, which of the following statements could explain why?
PI3 + 3H2O H3PO3 + 3HI
Stoichiometry : DeterMolesInRxn (4 Variations)   
(Assessment Material (1))
The reaction of zinc with aqueous hydrochloric acid has the following unbalanced equation

Zn(s) + HCl(aq) ArrowZnCl2(aq) + H2(g)

When 0.1 moles of zinc is reacted with 0.1 moles of hydrochloric acid ...

Stoichiometry : CalcTheorYield (10 Variations)   
(Assessment Material (1))
If you react 6.2g of phosphine with 8.30g of oxygen, what is the theoretical yield of phosphorous pentaoxide?

4PH3 + 8O2 P4O10 + 6H2O

Stoichiometry : DiagramRxnProds (6 Variations)   
(Assessment Material (1))
According to the law of conservation of matter, which of the following diagrams represents possible products of the following reaction?

A2 + 2B2

Stoichiometry : BalanceRxn (14 Variations)   
(Assessment Material (1))
The reaction of methane with oxygen has the following unbalanced equation

CH4(g) + O2(g) CO2(g) + H2O(l)

The coefficient for oxygen in the balanced equation is ...

Stoichiometry : RxnNanoPics (4 Variations)   
(Assessment Material (1))
The following diagram shows a compound reacting to form products. Which equation best describes the stoichiometry of the reaction shown in the diagram?

Stoichiometry : GeneralMassMole (4 Variations)   
(Assessment Material (1))
10.0 g of nitrogen monoxide is reacted with 10.0 g of oxygen to form nitrogen dioxide. Which of the following statements is true?
Stoichiometry : EmpirFormulaFromRxn (10 Variations)   
(Assessment Material (1))
When one mole of a diatomic gas, Y2(g), reacts with one mole of hydrogen gas, neither gas is left over. What is the empirical formula of the compound formed?
Stoichiometry : CalcWeightPercent (8 Variations)   
(Assessment Material (1))
What is the weight percent of oxygen in LiHCO3?
Stoichiometry : CalcPercentYield (8 Variations)   
(Assessment Material (1))
When copper is heated in air, copper(II) oxide is formed. In a given experiment, 1.50 g copper was heated to yield 1.76 g copper(II) oxide. What is the percent yield?
Gases : VolGasReactInTorch (10 Variations)   
(Assessment Material (1))
Oxyacetylene torches used in high-temperature welding use a combination of oxygen and acetylene. The combustion of acetylene (C2H2) occurs in these torches. What volume of oxygen is needed to react with 250 mL of acetylene?
Stoichiometry : LimitingReagent (8 Variations)   
(Assessment Material (1))
The synthesis of urea by Frederich W??hler in 1825 began the decline of the idea that "organic" chemicals could only be made by living organisms as part of their biological processes.

AgOCN(aq) + NH4Cl(aq)AgCl(s) + NH2CONH2(aq)

If you perform this reaction and collect the following table of data, in which trial(s) is AgOCN clearly the limiting reactant?

Trial AgOCN used NH4Cl AgCl produced
1 20.4 mL 5.3 mL 2.4 g
2 20.3 mL 10.4 mL 4.3 g
3 20.6 mL 15.4 mL 6.2 g
4 20.5 mL 20.6 mL 8.2 g
5 20.4 mL 25.2 mL 10.2 g
6 20.3 mL 30.4 mL 10.3 g

The mL of AgOCN and NH4Cl are the initial amounts used, the mass of AgCl is how much was recovered from the reaction. (Hint: You do not need to do any calculations to answer this question.)

Atoms,_Molecules_and_Ions : MassInAlloy (10 Variations)   
(Assessment Material (1))
Gold is alloyed with other metals to make it less malleable. 10 karat gold is an alloy that is 41.7% gold. How much pure gold is in a 20. gram 10 karat gold ring?
Stoichiometry : StoicNeeds (10 Variations)   
(Assessment Material (1))
You have a known mass of a compound X and react it to form compound Y. What is the minimum information you need to find the mass of Y produced?
Stoichiometry : GramMoleProblem (9 Variations)   
(Assessment Material (1))
Which sample contains the largest number of nitrogen atoms?
Anthropology and Protein Stoichiometry   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Limiting Reagent Protein Nutrition   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Analysis of CHO Compounds   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Optimizing Gunpowder Composition   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Atom Efficiency and the 2006 Presidential Green Chemistry Award   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Hydrogen Powered Bicycles Run on Water   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Why Fats Don't Add Up on Food Nutrition Labels   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Synthesis of Biodiesel Fuel   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Vegetable Oil Hydrogenation, Trans Fats, and Percent Yield   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Gunpowder Explosion Stoichiometry and Gunshot Residue (GSR)   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Fertilizers, Formulas, and Ecological Stoichiometry   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Burning...or Metabolizing...Fats and Sugars   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Using the Acid Test to Distinguish the Minerals in Calomine   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Synthesis of Superconductors   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Laboratory Synthesis of the Mineral Hedenbergite   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Balancing Equations for Carbohydrate Reactions   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Equations Related to Food Additives   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Sodium Silicide Fueled Bicycles   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Rocket Propellants   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Equations and Mass Relationships in Biology-Ecological (Biological) Stoichiometry   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Equations and Mass Relationships in Biology-Metabolism of Dietary Sugar   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Equations and Mass Relationships in Foods,Metabolism of Dietary Sugar   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Varieties of Salt and Salt Additives   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Iron Supplements and Iron Overload   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Equations and Mass Relationships Lecture Demonstrations   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Formulas and Composition Lecture Demonstrations   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Percent Yield-Synthetic Sweeteners   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Limiting Reagent Lecture Demonstrations   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
TSP, Ecological Stoichiometry, and Algal Blooms   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Berthollides-A Challenge to Chemical Stoichiometry   
()
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.