Chem 8.1-9.6
3H2 (g) + N2 (g) → 2NH3 (g) Calculate the mass of NH3 produced by the complete reaction of 2.55 g of H2 with excess N2 according to the equation above. 21.5 g 1.70 g 1.69 g 14.4 g
14.4 g
A 2.26-M solution of KOH is prepared. Calculate the moles and mass of solute present in a 15.2-mL sample of this solution. The molar mass of KOH is 56.11 g/mol. 8.36 g 0.149 moles 3.44 × 10-2 moles 1.93 g 6.73 × 10-3 moles
3.44 × 10-2 moles 1.93 g
Starting with a stock solution of HCl with a concentration of 6.0 M, four solutions are prepared by serial dilution. At each stage, 10.0 mL of solution is diluted to 250.0 mL. The solutions are labeled 1 (stock solution), 2 (first diluted solution), 3 (second diluted solution), and 4 (final solution). What is the concentration of solution 4? 3.8 × 10-4 M 9.6 × 10-3 M 0.24 M 9.4 × 10-2 M
3.8 × 10-4 M
True or false: The term "weak" can be used to describe a solution that has a small ratio of solute to solvent.
false
A chemical equation is a statement using chemical _____________ that expresses both the identities and the relative _______________ of the reactants and products involved in a chemical or physical change.
formula, quantity
A method of quantitative analysis that is based on the measurement of mass, and which often employs precipitation reactions, is known as ________ analysis.
gravimetric
When a strong acid reacts with a strong base, the products are typically a(n) compound, which is called a(n) , and the neutral molecule .
ionic, salt, water
Aqueous solutions of soluble ionic substances and acids conduct an electric current because, in solution, both compounds produce ________, which are free to move.
ions
The double arrows in the balanced equation given indicate that the reaction of a weak acid with water is ___________. A weak acid exists in _____________ with its ions in solution. (Provide a one-word answer for each blank.)
reversible, equilibrium
An ionic compound that results from the reaction of an acid and a base is called a(n) __________. The cation in this compound comes from the __________ while the anion comes from the ________.
salt, base, acid
Very dilute solutions are often prepared by diluting a stock solution, and then diluting the diluted solution further. This process is called __________ dilution and is often used to prepare a series of solutions of known concentrations.
serial
A 6.0 molar stock solution of HCl (aq) undergoes three successive tenfold dilutions to prepare a solution whose concentration is 6.0 x 10-3 M. This is an example of a general process known as ______ successive decomposition serial dilution dilutive preparation microdilution
serial dilution
A precipitation reaction is a reaction in which two or more water-_________ ionic compounds react in aqueous solution to form a(n) __________ precipitate.
soluble, insoluble
In a solution, the substance present in the largest quantity is called the ___________, while any other dissolved components are called ____________
solvent, solute
A solution is diluted by adding more _____, which means the _____ of the solution increases but the amount (moles) of solute stays the same. solvent; concentration solute; concentration solute; volume solvent; volume
solvent; volume
An acid-base reaction is also called a(n) _______ reaction because in many cases the product is a neutral solution of a soluble _________ compound, also called a salt.
neutralization, ionic
The quantity -log[H3O+] is called the _________ of a solution.
pH
True or false: The equation shown is used for calculations involving the dilution of solutions. Md x Ld = Mc x Lc
true
The volume of 2.050 M copper(II) nitrate that must be diluted with water to prepare 750.0 mL of a 0.8543-M solution is equal to mL. Report your answer to 4 significant figures in decimal notation (not scientific or exponential notation). Listen to the complete question
312.5
Which arrow shown is used to depict a reaction that reaches dynamic equilibrium rather than converting all reactants to products? A B C
C
What is the concentration of a solution (in M) prepared by diluting 37.00 mL of 0.250 M potassium chloride to 150.00 mL? Multiple choice question. 0.0617 M 1.01 M 1.62 M
0.0617
Given the balanced equation below, determine the moles of HCl required and the mass of AgCl formed from the complete reaction of 18.3 g of Ag2S. Ag2S (s) + 2HCl (aq) → 2AgCl (s) + H2S (g) 10.6 g of AgCl 7.38 × 10-2 mol HCl 0.148 mol HCl 21.2 g of AgCl
0.148 mol HCl 21.2 g of AgCl
A solution contains K+ and CO32- ions. If [K+] = 0.44 M and [CO32-] = 0.22 M, what was the concentration of the K2CO3 when the solution was prepared? 0.11 M 0.22 M 0.66 M 0.44 M
0.22 M
250. mL of an aqueous solution of AgNO3 of unknown concentration is treated with an excess of NaBr solution in order to precipitate the silver ions, and 11.3 g of AgBr (s) is recovered from the reaction. What is the concentration of the AgNO3 solution? 0.060 M 0.240 M 0.419 M 0.105 M
0.24
1- determine the moles or reactants 2- determine the amount of product 3- identify the limiting reactant 4- multiply the number of moles
1- determine the moles or reactants 2- determine the amount of product 3- identify the limiting reactant 4- multiply the number of moles
B2 + 2AB → 2AB2 In the balanced reaction equation above, if 1.0 moles of B2 and 1.5 moles of AB are allowed to react to completion, what is the maximum amount of AB2 that can form? 1.5 moles 2.0 moles 2.5 moles 0.75 moles
1.5 moles
2S (s) + 3O2 (g) → 2SO3 (g) Which of the following gives the correct setup for calculating the number of moles of SO3 that will form from the complete reaction of 1.5 mol of O2, according to the balanced reaction equation above? 1.5/2×3 1.5×2/3 1.5×3/2 1.5 × 3 × 2
1.5×2/3
What is the concentration of H3O+ in a solution whose pH is equal to 8.0? 8.0 M 10-8 M -0.90 M 108 M
10-8 M
The pH scale is a logarithmic scale, meaning that a solution with a pH of 1.00 has a concentration of hydronium (H3O+) _____ times _____ than a solution with a pH of 3.00. 2; greater 100; greater 2; less 100; less
100; greater
When the following chemical equation is balanced correctly, what is the correct coefficient for each species? (Enter ALL numbers, including the digit 1, if required.) SO2(g) + O2 (g) → SO3 (g) SO2 O2 SO3
2, 1, 2
Butane burns in oxygen according to the following balanced reaction equation: 2C4H10 (g) + 13O2 (g) → 8CO2 (g) + 10H2O (g) When a 5.6-mole sample of butane reacts with O2, which of the following amounts of other reaction species are correct? 56 moles H2O 22 moles CO2 36 moles O2
22 moles CO2 36 moles O2
Select all the conversion factors that correctly represent the molar relationships in this balanced equation 2Al + 3Cl2 → 2AlCl3.
2mol AlCl3/ 2mol Al 2mol Al/ 3mol Cl2
When hydrogen gas is passed over powdered iron(III) oxide, iron metal and water vapor are formed. Select the correct balanced equation for this process. 2H (g) + Fe3O (s) → 3Fe (s) + H2O (g) 6H (g) + Fe2O3 (s) → 2Fe (s) + 3H2O (g) H2 (g) + Fe3O (s) → 3Fe (s) + H2O (g) 3H2 (g) + Fe2O3 (s) → 2Fe (s) + 3H2O (g)
3H2 (g) + Fe2O3 (s) → 2Fe (s) + 3H2O (g)
A reaction is expected to produce 83.5 g of CaCO3. The percent yield is recorded as 62.5%. What is the actual mass of CaCO3 obtained? 74.9 g 134 g 52.2 g
52.2 g
Place the following pH values in order of increasing [H3O+]. Start with the pH that corresponds to the lowest [H3O+] at the top of the list.
8.5 7.2 4.3
A particular reaction is expected to yield 125 g of Ca. The actual amount of Ca obtained is equal to 105 g. Calculate the % yield for the reaction. 16.0% 84.0% 119% 0.840%
84.0%
Which of the following correctly defines a precipitate? An aqueous solution that forms from a solid A soluble ionic compound A liquid that forms in a reaction A solid product that separates from a solution
A solid product that separates from a solution
Select all the statements that correctly describe a solution. A solution may have more than one solute. The solute is the substance present in the largest quantity. Not all solutions are liquid. A solution is a mixture of substances dissolved in water. A solution is a homogeneous mixture of two or more substances.
A solution may have more than one solute. Not all solutions are liquid. A solution is a homogeneous mixture of two or more substances.
Select all the statements that correctly describe the behavior of electrolytes and nonelectrolytes. A nonelectrolyte is a substance that does not dissolve in water. An electrolyte conducts an electric current when in the solid phase. An electrolyte is a substance that produces ions when dissolved in water. Nonelectrolytes are water-soluble molecular compounds.
An electrolyte is a substance that produces ions when dissolved in water. Nonelectrolytes are water-soluble molecular compounds.
Select the equation that correctly represents the ionization of the weak base CH3NH2 in water. CH3NH2 (l) + H2O (l) ⇌ CH3NH3+ (aq) + OH- (aq) CH3NH2 (l) + H2O (l) ⇌ CH3NH- (aq) + H3O+ (aq) CH3NH2 (l) + H2O (l) ⇌ +CH4NH2 (aq) + OH- (aq) CH3NH2 (l) + H2O (l) ⇌ CH3OH (aq) + NH3 (aq)
CH3NH2 (l) + H2O (l) ⇌ CH3NH3+ (aq) + OH- (aq)
Which of the following statements are correct interpretations of the balanced equation 4C (s) + S8 (s) → 4CS2 (l)? Select all that apply. 4 grams of carbon react with 1 gram of S8 to form 4 grams of CS2. Carbon and S8 are reactants and CS2 is the product. 4 moles of carbon react with 1 mole of S8 to form 4 moles of CS2. 4 atoms of carbon react with 1 molecule of S8 to form 4 molecules of CS2.
Carbon and S8 are reactants and CS2 is the product. 4 moles of carbon react with 1 mole of S8 to form 4 moles of CS2. 4 atoms of carbon react with 1 molecule of S8 to form 4 molecules of CS2.
Which of the following are among the species present in solution when the weak acid HClO dissolves in H2O? Cl- ClO- HClO OH-
ClO- HClO
Select all the statements that correctly describe how to classify a given compound as a nonelectrolyte, strong electrolyte, or weak electrolyte on the basis of its formula. A molecular compound is always a nonelectrolyte. Compounds related to NH3 are weak electrolytes. Any weak acid is a weak electrolyte. If the compound contains a cation and an anion, it is a strong electrolyte if it is soluble in water. All acids are strong electrolytes.
Compounds related to NH3 are weak electrolytes. Any weak acid is a weak electrolyte. If the compound contains a cation and an anion, it is a strong electrolyte if it is soluble in water.
Which of the following steps would be required to convert between the masses of two substances that are related through a chemical reaction? (For example, calculating the mass of product formed from the mass of a reactant.) Select all that apply. Convert from the given mass to moles of the same substance. Calculate the molar masses of all substances in the reaction. Write a balanced chemical equation for the reaction. Use the coefficients from the balanced equation to convert directly from the mass of one substance to the other. Write a conversion factor using the coefficients from the balanced equation, and convert to moles of the second substance.
Convert from the given mass to moles of the same substance. Write a balanced chemical equation for the reaction. Write a conversion factor using the coefficients from the balanced equation, and convert to moles of the second substance.
Which of the substances below are represented with their proper formulas? Elemental sodium, Na+ Elemental oxygen, O2 Elemental boron, B2 Elemental copper, Cu Elemental phosphorus, P4
Elemental oxygen, O2 Elemental copper, Cu Elemental phosphorus, P4
True or false: In order to balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid H2O, a student adds a subscript of 2 to H2O (forming H2O2). This is an acceptable method of balancing the reaction described.
False
Select all the options that correctly describe gravimetric analysis. Gravimetric analysis is used in any reaction where reactants and products are solids. In this technique, the concentration of one solution is determined by reaction with a second solution. Gravimetric analysis is based on the measurement of mass. Precipitation reactions are often used in gravimetric analysis. Gravimetric analysis may be used to determine the concentration of an ion in solution.
Gravimetric analysis is based on the measurement of mass. Precipitation reactions are often used in gravimetric analysis. Gravimetric analysis may be used to determine the concentration of an ion in solution.
Which equation is a correct representation of the reaction shown? In the illustration, carbon is black, oxygen is red, and hydrogen is white. H2 + CO3 → CO2 + H2O H2CO3 → CO2 + H2O 2H + 3O + C → CO2 + 2H + O
H2CO3 → CO2 + H2O
Select the options that correctly identify the products for the acid-base reaction shown. Ca(OH)2 (aq) + H2SO4 (aq) → SO42- (aq) H2O (l) Ca2+ (aq) H3O+ (aq) CaSO4 (s)
H2O (l) CaSO4 (s)
Which of the following statements correctly interpret the balanced chemical equation 4HCl (aq) + MnO2 (s) → MnCl2 (aq) + 2H2O (l) + Cl2 (g)? Select all that apply. HCl is a reactant in this equation. Water is both a solvent and a product in this reaction. The MnO2 used in this reaction is a solution. The MnCl2 produced is dissolved in water. 4.00 g of HCl reacts with 1.00 g of MnO2.
HCl is a reactant in this equation. Water is both a solvent and a product in this reaction. The MnCl2 produced is dissolved in water.
Which of the following are strong acids? Select all that apply. HClO4 HF H2SO4 HBr HNO2
HClO4 H2SO4 HBr
Which of the following options gives the correct net ionic equation for the reaction between an aqueous solution of the weak acid HNO2 and aqueous lithium hydroxide, LiOH? HNO2 (aq) + LiOH (aq) → H2O (l) + LiNO2 (aq) H3O+ (aq) + OH- (aq) → 2H2O (l) HNO2 (aq) + OH- (aq) → H2O (l) + NO2- (aq) H+ (aq) + NO2- (aq) + Li+ (aq) + OH- (aq) → H2O (l) + Li+ (aq) + NO2- (aq)
HNO2 (aq) + OH- (aq) → H2O (l) + NO2- (aq)
Which of the following actions are permitted in balancing a chemical equation? Altering the formulas of reactants or products Inserting coefficients before the formulas of reactants and products Inserting a coefficient between two elements in the formula of a compound Multiplying all coefficients by a common factor Adding reactants or products
Inserting coefficients before the formulas of reactants and products Multiplying all coefficients by a common factor
Of the elements listed, select all that typically occur as diatomic molecules. Sulfur Helium Iodine Nitrogen Carbon
Iodine Nitrogen
Which is the correct equation to use when performing calculations involving the dilution of a solution? Mc/Lc = Md/Ld Mc × Lc = Md × Ld Lc/Mc = Ld/Md Mc × Vd = Md × Lc
Mc × Lc = Md × Ld
"Aqueous solutions of calcium hydroxide and sodium phosphate react to form aqueous sodium hydroxide and solid calcium phosphate." In the reaction represented by the statement above, what are the reactants? Ca3(PO4)2 Na3PO4 Ca(OH)2 NaOH H2O
Na3PO4 Ca(OH)2
Select all the statements that correctly describe the behavior of different types of substances in aqueous solution. Nonelectrolytes produce no ions in solution. Glucose (C6H12O6) is a nonelectrolyte and produces no solute particles when dissolved in water. Strong electrolytes always produce concentrated solutions. Acetic acid is a weak electrolyte. When this substance is dissolved in H2O there will be a mixture of HC2H3O3 molecules, C2H3O2- ions, and H+ ions. MgCl2 is a strong electrolyte and will dissociate to produce ions in aqueous solution.
Nonelectrolytes produce no ions in solution. Acetic acid is a weak electrolyte. When this substance is dissolved in H2O there will be a mixture of HC2H3O3 molecules, C2H3O2- ions, and H+ ions. MgCl2 is a strong electrolyte and will dissociate to produce ions in aqueous solution.
In a balanced chemical equation, which of the following must be the same on both sides of the equation? Number of molecules Number of atoms of each element Phase labels Potential energy
Number of atoms of each element
Which of the elements listed below appear as polyatomic molecules in their standard states? Select all that apply. Oxygen Fluorine Hydrogen Neon Beryllium
Oxygen Fluorine Hydrogen
Which of the elements listed below appear as polyatomic molecules in their standard states? Select all that apply. Argon Phosphorus Magnesium Nitrogen
Phosphorus Nitrogen
A compound is described as a strong acid. What does this term mean? (Select all that apply.) The molecules of the compound are strongly bonded and do not ionize. The molecules of the compound hold tightly to their H atoms. The compound ionizes completely in water. The molarity of the solution is high. There are essentially no intact molecules of the compound remaining in solution.
The compound ionizes completely in water. There are essentially no intact molecules of the compound remaining in solution.
Which of the following statements correctly describe the limiting reactant in a reaction? Select all that apply. The limiting reactant limits the amount of product that can form. The moles of product formed will always be equal to the moles of the limiting reactant given in the problem. There will always be limiting reactant left over after the reaction is complete. The maximum amount of product formed is the amount that can be formed from the limiting reactant. The limiting reactant is always the reactant present in the lowest mass amount.
The limiting reactant limits the amount of product that can form. The maximum amount of product formed is the amount that can be formed from the limiting reactant.
A chemistry problem states that [SO42-] = 0.25 M. What does this mean? The total number of moles of SO42- ions in the volume provided is equal to 0.25. There are 0.25 g of SO42- per L of solution. The molar concentration of SO42- is 0.25 moles per L.
The molar concentration of SO42- is 0.25 moles per L.
Which of the following statements correctly describe the changes occurring during a dilution? Select all that apply. The total volume of the solution will not change. The number of moles of solvent will not change. The number of moles of solute will not change. The concentration of the solution decreases. The concentration of the solution increases.
The number of moles of solute will not change. The concentration of the solution decreases.
150.0 mL of a solution containing Ba2+ ions is analyzed by adding 0.18 M Na2SO4 solution until no more precipitate forms. The mass of BaSO4 precipitate obtained is 11.20 g. Select all the options that correctly reflect the steps required to calculate the concentration of Ba2+ in the original solution. Multiple select question. The original solution contained 4.80 x 10-2 moles of Ba2+. The concentration of Ba2+ is equal to 0.18 M. The molar mass of BaSO4 is 233.4 g/mol. The concentration of Ba2+ ions is equal to 0.320 M. The original solution contained 0.0270 moles of Ba2+ ions.
The original solution contained 4.80 x 10-2 moles of Ba2+. The molar mass of BaSO4 is 233.4 g/mol. The concentration of Ba2+ ions is equal to 0.320 M.
Select all the statements that correctly describe steps in the procedure used to identify a limiting reactant. The maximum product possible is given by the sum of the amounts of product formed from each reactant. The reactant that produces the least amount of possible product is the limiting reactant. The reactant that has the highest mass at the beginning of the reaction is in excess. Calculate the amount of product that could be formed from each reactant. Calculate the molar masses of any reactants for which a mass has been given.
The reactant that produces the least amount of possible product is the limiting reactant. Calculate the amount of product that could be formed from each reactant. Calculate the molar masses of any reactants for which a mass has been given.
Which of the following options correctly describe the products of the reaction between a strong acid and a strong base in aqueous solutions? Select all that apply. The reaction forms a salt and water. The reaction usually produces an insoluble precipitate. There is no net ionic equation as all species are soluble in water. The reaction produces H3O+ and OH- ions. The net ionic equation is typically given by H+ (aq) + OH- (aq) → H2O (l).
The reaction forms a salt and water. The net ionic equation is typically given by H+ (aq) + OH- (aq) → H2O (l).
Which of the following statements describe the information that can be gained from a balanced chemical equation? Select all that apply. How fast a given reaction proceeds. The relative quantities (moles) of the substances involved. The physical states of reactants and products, usually. The temperature at which a reaction is carried out. The identities of substances involved.
The relative quantities (moles) of the substances involved. The physical states of reactants and products, usually. The identities of substances involved.
Starting with a stock solution of NaCl with a molarity of 0.880 M, four solutions are prepared by serial dilution. At each stage, 15.0 mL of solution is diluted to 100.0 mL. The solutions are labeled 1 (stock solution), 2 (first diluted solution), 3 (second diluted solution), and 4 (final solution). Select all the statements that correctly describe the solutions prepared. The second diluted solution (solution 3) has a concentration of 0.0198 M. There are 0.880 moles of solute in the stock solution. There are 1.32 × 10-2 moles of NaCl in the first diluted solution (solution 2). The final solution has a concentration of 0.0440 M.
The second diluted solution (solution 3) has a concentration of 0.0198 M. There are 1.32 × 10-2 moles of NaCl in the first diluted solution (solution 2).
Why does an aqueous solution of an ionic substance conduct an electric current? The solution contains ions that are free to move. Water conducts electricity. An ionic substance contains a metal, and metals conduct electricity. The solution contains free electrons that can carry a current.
The solution contains ions that are free to move.
Select all the statements that correctly describe the symbols used to write a balanced equation. The symbol (s) indicates that a substances is in solution. The symbol (g) indicates a substance in the gas phase. The transformation of reactants into products is represented with an equal sign, =. Reactants or products that are dissolved in water are given the symbol (l). The symbol (s) is used for a powdered substance.
The symbol (g) indicates a substance in the gas phase. The symbol (s) is used for a powdered substance.
Which of the following options correctly describe a precipitation reaction? Select all that apply. The reaction involves a transfer of electrons between reactants. This type of reaction usually involves ionic compounds. The reactants are insoluble precipitates. This type of reaction forms one or more insoluble products. This type of reaction often occurs in aqueous solution.
This type of reaction usually involves ionic compounds. This type of reaction forms one or more insoluble products. This type of reaction often occurs in aqueous solution.
True or false: pH is a measure of hydronium ion concentration.
True
Which of the following correctly represents the molar concentration of Ca2+ ions in an aqueous solution of CaCl2? ΙCa2+Ι (Ca2+) {Ca2+} [Ca2+]
[Ca2+]
Which of the following gives the correct mathematical operation required to calculate the [H3O+] given a pH of 5.0? [H3O+] = 5.0 [H3O+] = -log(5.0) [H3O+] = 10-5.0 [H3O+] = 105.0
[H3O+] = 10-5.0
Select the options that correctly identify the concentrations of the individual ions present in a solution that is 0.14 M in ZnCl2. [Zn2+] = 0.070 M [Cl-] = 0.070 M [Cl-] = 0.14 M [Zn2+] = 0.14 M [Cl-] = 0.28 M
[Zn2+] = 0.14 M [Cl-] = 0.28 M
A neutralization reaction occurs between a(n) _________ and a(n) __________.
acid, base
A(n) ________ is a substance that produces H+ ions when dissolved in water, whereas a(n) ________ produces OH- ions in aqueous solution.
acid, base
A salt is an ionic product of an acid-base neutralization reaction whose cation comes from the ______ and whose anion comes from the ______. base; acid base; water acid; base water; acid
base; acid
concentration- the amount concentrated- __ large amount dilute- __ small amount
concentration- the amount concentrated- __ large amount dilute- __ small amount
Soluble ionic compounds, acids, and molecular bases all produce ions in solution. An ionic compound will _________ in aqueous solution, breaking apart into its component ions. Acids and molecular bases will _______ in water, producing ions even though they are molecular compounds.
dissociate, ionize
dissociation -> ionic compound.... ionization -> a molecular compound....
dissociation -> ionic compound.... ionization -> a molecular compound....
A substance that conducts electricity when dissolved in water is called a(n) ___________; whereas a substance that does not conduct electricity in aqueous solution is a(n) _________
electrolyte, nonelectrolyte
The ________ reactant in a reaction is one that limits the amount of product formed. This reactant will be completely used up in the reaction. Any reactants that are not used up are said to be ________ reactants.
limiting, excess
The higher the pH value, the _____ the [H3O+] and the _____ acidic the solution will be. Multiple choice question. higher; more higher; less lower; more lower; less
lower; less
The concentration of a solution expressed in moles of solute per 1 L of solution is called either the ________ or the ________ concentration, and is given the symbol M.
molarity, molar
Which of the following is the correct expression for the molarity of a solution? moles of solute/ liters of solvent moles of solute/ kilograms of solvent moles of solvent/ liters of solution moles of solute/ liters of solution
moles of solute/ liters of solution
An insoluble product (i.e., a solid) that forms from a reaction in solution is called a(n) _________
precipitate
N2O4 → 2NO2 In the reaction represented by the chemical equation above, NO2 is the formula of the ______ and N2O4 is the formula of the ______. reactant, product product, reactant
product, reactant