Chemistry MC: May 2020

Archive for May 2020

Which classification of elements on the periodic table does not combine chemically with other elements?

Which classification of elements on the periodic table does not combine chemically with other elements? A) Non-metals B) Metals C) Noble gases D) Transitions Answer: C)...

Any atom, except hydrogen and helium, is considered chemically stable when there are how many electrons in the outermost shell?

Any atom, except hydrogen and helium, is considered chemically stable when there are how many electrons in the outermost shell? A) 5 B) 3 C) 2 D) 8 Answer: D)...

What type of chemical bond is usually formed between atoms that readily give up electrons and atoms that readily accept electrons?

What type of chemical bond is usually formed between atoms that readily give up electrons and atoms that readily accept electrons? A) Ionic B) Transitional C)...

Atoms that have become charged from losing or gaining electrons are called ______.

Atoms that have become charged from losing or gaining electrons are called ______. A) Anodes B) Molecules C) Ions D) Pairs Answer: C) Io...

All of the elements in a vertical column of the periodic table have ______.

All of the elements in a vertical column of the periodic table have ______. A) Eight electrons in the outermost shell B) Identical numbers of protons C)...

Two or more elements combine chemically to form a _______.

Two or more elements combine chemically to form a _______. A) Substance B) Mixture C) Composite D) Compound Answer: D) Compou...

What happens in a single displacement reaction?

What happens in a single displacement reaction? A) A single element decomposes into new elements B) Two or more different reactants combine to form...

The quantity of an element that has a weight in grams numerically equal to the element's atomic weight is called _______.

The quantity of an element that has a weight in grams numerically equal to the element's atomic weight is called _______. A) A carbon ratio B) The...

When the maximum amount of solute that the solvent can dissolve is added, it is called a ______ solution.

When the maximum amount of solute that the solvent can dissolve is added, it is called a ______ solution. A) Polar B) Saturated C) Combination D) Concentrated Answer: B)...

The nucleus of an atom is comprised of ______.

The nucleus of an atom is comprised of ______. A) Electrons B) Ions and electrons C) Anions D) Protons and neutrons Answer: D) Protons and ...

The notation that expresses the number of electrons involved when an atom reacts chemically is the ______ number.

The notation that expresses the number of electrons involved when an atom reacts chemically is the ______ number. A) Combination B) Period C) Reaction D)...

What type of chemical bond is formed when electrons are shared between atoms?

What type of chemical bond is formed when electrons are shared between atoms? A) Noble B) Transitional C) Covalent D) Ionic Answer: C) Cova...

Which of these is the best way to express the formula HOH?

Which of these is the best way to express the formula HOH? A) HHO B) 2HO C) 2H1O D) H20 Answer: D) H...

Which classification of elements on the periodic table tends to give up electrons when combining chemically with other elements?

Which classification of elements on the periodic table tends to give up electrons when combining chemically with other elements? A) Noble gases B)...

When a compound is formed, the total of all the valences must equal _____.

When a compound is formed, the total of all the valences must equal _____. A) 1 B) 0 C) 2 D) 100 Answer: B)...

What happens in a decomposition reaction?

What happens in a decomposition reaction? A) A compound breaks down into the compounds or elements that formed it B) Two or more different reactants...

Most water solutions can conduct electricity to varying degrees and are called ______ solutions.

Most water solutions can conduct electricity to varying degrees and are called ______ solutions. A) Saturated B) Electrolyte C) Galvanic D) Cathodic Answer: B)...

Which of the following is a correct way to write chemical equations?

Which of the following is a correct way to write chemical equations? A) Products are shown only if they are gases B) Reactants are shown to the right...

What is the smallest particle of an element that still retains the chemical properties of that element?

What is the smallest particle of an element that still retains the chemical properties of that element? A) Atom B) Neutron C) Electron D) Proton Answer: A)...

Water will dissolve ionic compounds because____________.

Water will dissolve ionic compounds because____________. A) Water takes electrons away from the ions B) The ions are much smaller than the water molecules C)...

In a titration experiment, if the initial solution pH is 4.0 and the equivalence point occurs at pH 9.0, then the reaction corresponds to

In a titration experiment, if the initial solution pH is 4.0 and the equivalence point occurs at pH 9.0, then the reaction corresponds to a. the titration...

Which indicator is most appropriate for the titration of acetic acid ? (Ka = 1.8 105) with NaOH

Which indicator is most appropriate for the titration of acetic acid ? (Ka = 1.8 105) with NaOH a. methyl red (pH 5) b. bromthymol blue (pH 7) c....

In a titration of HCl(aq) with NaOH(aq), the equivalence point is the point at which equal volumes of HCl and NaOH have been combined.

In a titration of HCl(aq) with NaOH(aq), the equivalence point is the point at which equal volumes of HCl and NaOH have been combined. the concentration...

What is the effect on pH when a buffer is diluted by a factor of 10? The buffer pH deceases by 10.

What is the effect on pH when a buffer is diluted by a factor of 10? The buffer pH deceases by 10. The buffer pH decreases by 1. The buffer pH decreases...

When mixed together, all of the following pairs can form buffers EXCEPT

When mixed together, all of the following pairs can form buffers EXCEPT a.H3PO4 and NaH2PO4. b.NaH2PO4 and Na2HPO4. c.NaI and NaOH. d.HCl and NaCH...

Which of the following chemical equations corresponds to Kb1 for SO32-?

Which of the following chemical equations corresponds to Kb1 for SO32-? a. HSO3-(aq) + H2O(l) b. SO32-(aq) + H3O+(aq) c. H2SO3(aq) + OH-(aq) d. SO32-(aq)...

Which of the following reactions are acid-base reactions according to the Brønsted-Lowry model?

Which of the following reactions are acid-base reactions according to the Brønsted-Lowry model? 1. NH4+(aq) + H2O(l) NH3(aq) + H3O+(aq) 2. 2HF(aq)...

All of the following species are amphiprotic EXCEPT

All of the following species are amphiprotic EXCEPT a. H2O. b. HSO4- c. HPO42- d. SO42- Answer: ...

What is the conjugate acid of ammonia?

What is the conjugate acid of ammonia? a.H+ b. H- c.NH4+ d.NH3 Answer: ...

According to the Brønsted-Lowry definition, a base

According to the Brønsted-Lowry definition, a base a. is a proton acceptor. b. increases the OH- concentration in an aqueous solution. c. is an electron-pair...

The Haber process for the production of ammonia relies on a heterogeneous catalyst. How does the use of this catalyst affect the yield of the reaction at equilibrium?

The Haber process for the production of ammonia relies on a heterogeneous catalyst. How does the use of this catalyst affect the yield of the reaction...

The formation of ammonia from elemental nitrogen and hydrogen is an exothermic process. N2(g) + 3H2(g) 2NH3(g) H = 92.2 kJ/mol. Assuming the reaction is at equilibrium, which one of the following changes will drive the reaction to the right?

The formation of ammonia from elemental nitrogen and hydrogen is an exothermic process. N2(g) + 3H2(g) 2NH3(g) H = 92.2 kJ/mol.Assuming the reaction...

If the value of Q is less than K, then

If the value of Q is less than K, then a. the system is in equilibrium. b. the reaction will go left or right depending upon the reaction stoichiometry. c....

In which of the following equilibrium systems will an increase in the pressure have no effect on the concentrations of products and reactants?

In which of the following equilibrium systems will an increase in the pressure have no effect on the concentrations of products and reactants? a....

Assume that the following chemical reaction is at equilibrium.

Assume that the following chemical reaction is at equilibrium. 2ICl(g) I2(g) + Cl2(g) H = +26.9 kJ At 25C, K = 2.0 105. If the temperature is increase...

In a titration experiment, if the initial solution pH is 10.0 and equivalence point at pH 4.0, then reaction corresponds to

In a titration experiment, if the initial solution pH is 10.0 and equivalence point at pH 4.0, then reaction corresponds to a. WA and SB b.WA and WB c.WB...

Which indicator is most appropriate for the titration of ammonia with HCl?

Which indicator is most appropriate for the titration of ammonia with HCl? a. Methyl red b. Bromthymol blue c.Phenolphthalein d. Both red and Blue...

Which of the following statements concerning acid-base indicators are true?

Which of the following statements concerning acid-base indicators are true? 1. Acid Base indicators are derived from weak acids 2. The acid and base...

In a titration of HCl with NaOH, the equivalence point is the point at which

In a titration of HCl with NaOH, the equivalence point is the point at which a. equal volumes of HCL and NaOH have been combined b. the concentration...

What is the effect on pH when a Hclo4 is diluted by a factor of 10?

What is the effect on pH when a Hclo4 is diluted by a factor of 10? a. pH increases by 10 b. pH decreases by 1 c. pH increases by 1 d. pH does not...

A buffer may be prepared by mixing a weak acid with a certain amount of strong base. Which of the acids best for preparation of a buffer with pH of 7.00

A buffer may be prepared by mixing a weak acid with a certain amount of strong base. Which of the acids best for preparation of a buffer with pH of...

When mixed together, all of the following pairs can form buffers EXCEPT

When mixed together, all of the following pairs can form buffers EXCEPT a. H3PO4 and NaH2PO4- b. NaH2PO4 and Na2HPO2- c.H3PO4 and NaOH d. HCL and ...

According to the Lewis definition, a base

According to the Lewis definition, a base a. Is a proton acceptor b. Increases the OH- concentration in an aqueous solution c. Is an electron-pair...

Which of the following is a Lewis acid NOT a Bronstead-Lowry acid

Which of the following is a Lewis acid NOT a Bronstead-Lowry acid a. HF b.NH4+ c.ZN2+ d.HPO42- Answer: ...

A salt solution can be acidic, basic or neutral. When dissolved in water, which of the following will make the solution acidic: NaBr, Fe(NO3)3, BaCO3, and CrCl3

A salt solution can be acidic, basic or neutral. When dissolved in water, which of the following will make the solution acidic: NaBr, Fe(NO3)3, BaCO3,...

A salt solution can be acidic, basic or neutral. When dissolved in water, which of the following will make the solution basic: NaBr, KF, BaCO3, and CrCl3

A salt solution can be acidic, basic or neutral. When dissolved in water, which of the following will make the solution basic: NaBr, KF, BaCO3, and...

Which of the following chemical equations corresponds to Ka2 for H2SO3

Which of the following chemical equations corresponds to Ka2 for H2SO3 a. H2SO3-->HSO3-+H+ b. SO32-+H3O+--->HSO3-+H2O c.HSO3---->SO32-+H+ d....

Which of the following reactions are acid-base reactions according to Bronstead Lowry model?

Which of the following reactions are acid-base reactions according to Bronstead Lowry model? 1. NH4+ + H2O --->NH3+H3O+ 2.HF+NH3--->F-+NH4+ ...

What is conjugate acid of [Al(H20)5OH]^2+

What is conjugate acid of [Al(H20)5OH]^2+ a. [Al(H20)5]^3+ b.[Al(H20)5H3O]^4+ c.[Al(H20)6]^3+ d. H3O+ Answer: ...

All of the following species are amphiprotic EXCEPT

All of the following species are amphiprotic EXCEPT a. H20 b.Po43- c.H2PO4- d.HPO42- Answer: ...

Assuming the reaction below is at equilibrium which of the following changes will drive the reaction to the left?

Assuming the reaction below is at equilibrium which of the following changes will drive the reaction to the left? Co2(g)--->C(s)+O2(g) = +395.5...

Which of the following statements is CORRECT for the following system at equilibrium?

Which of the following statements is CORRECT for the following system at equilibrium? H2(g)+F2(g)---->2HF(g) a) Addition of catalyst will cause...

The formation of ammonia from elemental nitrogen and hydrogen is an exothermic process.

The formation of ammonia from elemental nitrogen and hydrogen is an exothermic process. N2(g)+3H2(g)--->2NH3(g) = -92.2KJ Assuming the reaction...

If the value of Q is greater than K, then

If the value of Q is greater than K, then a) The reaction will go left till equilibrium b) The reaction will go right till equilibrium c)The reaction...

Assume that the following chemical reaction is at equilibrium.

Assume that the following chemical reaction is at equilibrium. 2ICl(g)--->I2(g)+Cl2(g) =+26.9 kj a)K will increase and the reaction will go backwards b)K...

Which response includes all the acids listed below that are strong acids, and no weak acids?

Which response includes all the acids listed below that are strong acids, and no weak acids? H2SO4, HI, HF, H3PO4, HNO3 A. HI, HF, HNO3 B. H2SO4,...

Which response gives all of the members of the following list that are basic salts and none that are not basic salts?

Which response gives all of the members of the following list that are basic salts and none that are not basic salts? Al(OH)Cl2, Al(OH)2Cl, AlCl3,...

According to the Brønsted-Lowry theory, which of these acids would have the weakest conjugate base?

According to the Brønsted-Lowry theory, which of these acids would have the weakest conjugate base? A. HBrO3 B. HNO2 C. HClO4 D. HClO2 E. HF An...

Based on the reactions we have studied, ammonia can be considered as ____.

Based on the reactions we have studied, ammonia can be considered as ____. A. an Arrhenius base (only) B. a Lewis base (only) C. a Brønsted-Lowry...

For which one of the pairs of acid and bases does the following represent the correct net ionic equation?

For which one of the pairs of acid and bases does the following represent the correct net ionic equation? CH3COOH + OH− → CH3COO− + H2O A. NaOH,...

Which one of the following statements is true?

Which one of the following statements is true? CH 3NH 2 + H 2O --> CH 3NH 3+ + OH − methylamine, water methylammonium ion, hydroxide ion A. CH3NH2...

Write the net ionic equation for the complete neutralization of HBr by Ca(OH) 2. Use H + rather than H 3O +. What is the sum of the coefficients?

Write the net ionic equation for the complete neutralization of HBr by Ca(OH) 2. Use H + rather than H 3O +. What is the sum of the coefficients? A....

Write the balanced formula unit equation for the complete neutralization of dilute sulfuric acid with sodium hydroxide in aqueous solution. What is the sum of the coefficients?

Write the balanced formula unit equation for the complete neutralization of dilute sulfuric acid with sodium hydroxide in aqueous solution. What is...

Write the balanced formula unit equation for the reaction of iron(II) hydroxide with hydrobromic acid. What is the sum of the coefficients?

Write the balanced formula unit equation for the reaction of iron(II) hydroxide with hydrobromic acid. What is the sum of the coefficients? A. 6 B....

In the following reaction, the Cl − functions as a(n) ____.

In the following reaction, the Cl − functions as a(n) ____. AlCl3 + Cl− → AlCl4− A. Brønsted-Lowry acid B. Brønsted-Lowry base C. Arrhenius base D....

According to the Brønsted-Lowry theory, which of these anions is the strongest base?

According to the Brønsted-Lowry theory, which of these anions is the strongest base? A. NO3− B. Cl− C. CN− D. ClO4− E. HSO4− Answer: C...

Which one of the following is not a soluble, strong base?

Which one of the following is not a soluble, strong base? A. KOH B. CsOH C. NH3 D. Ca(OH)2 E. Sr(OH)2 Answer: N...

Which response gives all of the members of the following list that are acidic salts and none that are not acidic salts?

Which response gives all of the members of the following list that are acidic salts and none that are not acidic salts? KH2PO4, K2HPO4, K3PO4, NaHCO3,...

Why is HI a stronger acid than HCl?

Why is HI a stronger acid than HCl? A. Because I is more electronegative than Cl. B. Because Cl is more electronegative than I. C. The bond strength...

Which one of the following pairs of acids and conjugate bases is incorrectly labeled or incorrectly matched?

Which one of the following pairs of acids and conjugate bases is incorrectly labeled or incorrectly matched? Acid / Conjugate Base A. water / hydroxide B....

Which of the following statements is false?

Which of the following statements is false? A. Arrhenius acids are also Brønsted-Lowry acids. B. Brønsted-Lowry acids are also Lewis acids. C. Brønsted-Lowry...

According to the Brønsted-Lowry theory, which of these anions is the weakest base?

According to the Brønsted-Lowry theory, which of these anions is the weakest base? A. Br− B. ClO− C. NO2− D. F− E. CH3COO− Answer: B...

What is the basis for referring to "H +" as a proton?

What is the basis for referring to "H +" as a proton? A. The Arrhenius definition of an acid B. The Brønsted-Lowry definition of an acid C. The Lewis...

Which pair of acids would each react with barium hydroxide and have the net ionic equation:

Which pair of acids would each react with barium hydroxide and have the net ionic equation: H+ + OH− → H2O A. HCl and HNO2 B. HBr and HF C. HCl and...

Which one of the following is a weak acid?

Which one of the following is a weak acid? A. HNO3 B. H3PO4 C. HClO3 D. HClO4 E. HI Answer: H3P...

Which of the following reactions is the net ionic equation for the acid-base reaction between H 2CO 3 and Sr(OH) 2?

Which of the following reactions is the net ionic equation for the acid-base reaction between H 2CO 3 and Sr(OH) 2? A. H2CO3 + Sr2+ + 2OH− → SrCO3...

According to the Lewis theory, which one of the following compounds would be expected to react as a Lewis acid, but not as a Lewis base?

According to the Lewis theory, which one of the following compounds would be expected to react as a Lewis acid, but not as a Lewis base? A. BCl3 B....

In the equation HF + H2O H3O+ + F−

In the equationHF + H2O H3O+ + F− A. H2O is a base, and HF is its conjugate acid. B. H2O is an acid, and HF is the conjugate base. C. HF is an acid,...

Write the balanced net ionic equation for the complete neutralization of chromium(III) hydroxide with sulfuric acid. Use H + rather than H 3O +. What is the sum of the coefficients?

Write the balanced net ionic equation for the complete neutralization of chromium(III) hydroxide with sulfuric acid. Use H + rather than H 3O +. What...

Arrange the following in order of increasing acid strength:

Arrange the following in order of increasing acid strength: H2O, H2Se, H2Te, H2S A. H2O < H2Te < H2Se < H2S B. H2Se < H2Te < H2O <...

Which one of the following is a soluble, strong base?

Which one of the following is a soluble, strong base? A. Cu(OH)2 B. Fe(OH)3 C. Al(OH)3 D. Sr(OH)2 E. Mg(OH)2 Answer: Sr(OH...

Which one of the following species could not react as a Brønsted-Lowry base?

Which one of the following species could not react as a Brønsted-Lowry base? A. NH4+ B. NH2− C. CN− D. F− E. CH3COO− Answer: NH...

For which one of the pairs of acids and bases does the following represent the net ionic equation?

For which one of the pairs of acids and bases does the following represent the net ionic equation? H3O+ + OH− → 2H2O A. NaOH, HBr B. CH3COOH, Ca(OH)2 C....

According to the Lewis theory, a base ____.

According to the Lewis theory, a base ____. A. is a proton acceptor B. is a proton donor C. makes available a share in a pair of electrons D. is any...

According to the Lewis theory, which one of the following species would be expected to react as a Lewis base, but not as a Lewis acid?

According to the Lewis theory, which one of the following species would be expected to react as a Lewis base, but not as a Lewis acid? A. BF3 B. F− C....

Gaseous methylamine, CH 3NH 2, can be classified as ____.

Gaseous methylamine, CH 3NH 2, can be classified as ____. A. a Lewis base only B. Arrhenius and Brønsted-Lowry bases C. a Brønsted-Lowry base only D....

Which statement concerning the autoionization (self-ionization) of water is false?

Which statement concerning the autoionization (self-ionization) of water is false? 2H2O --> H3O+(aq) + OH−(aq) A. This reaction is an acid-base...

Which one of the following is a weak acid?

Which one of the following is a weak acid? A. H2SO4 B. HClO C. HCl D. HBr E. HI Answer: HC...

If a compound is able to react as either an acid or a base, it is said to be which of these?

If a compound is able to react as either an acid or a base, it is said to be which of these? A. autoionized B. amphoteric C. hydrated D. balanced E....

Which of the following is a normal salt?

Which of the following is a normal salt? A. Na3PO4 B. NaOH C. NaHCO3 D. NaHSO4 E. all of these are normal salts Answer: Na3P...

According to the Brønsted-Lowry theory, a base is defined as ____.

According to the Brønsted-Lowry theory, a base is defined as ____. A. an electron pair acceptor B. a proton acceptor C. an electron pair donor D....

Write the balanced formula unit equation for the reaction of hydrobromic acid with magnesium hydroxide. What is the sum of the coefficients?

Write the balanced formula unit equation for the reaction of hydrobromic acid with magnesium hydroxide. What is the sum of the coefficients? A. 6 B....

Examine the reaction below and classify it.

Examine the reaction below and classify it. FeBr3 + Br− → FeBr4− A. single displacement B. combustion C. decomposition D. acid-base E. oxidation...

Which one of the following compounds is not a salt?

Which one of the following compounds is not a salt? A. K2SO4 B. HClO4 C. CaCrO4 D. CoCl2 E. NaMnO4 Answer: HC...

Which of the following reactions represents and acid-base reaction according to Lewis theory but not according to Bronsted-Lowry theory?

Which of the following reactions represents and acid-base reaction according to Lewis theory but not according to Bronsted-Lowry theory? a) NH3 + HCl...

Which of the following could not act as a ligand in a complex ion with a transition metal?

Which of the following could not act as a ligand in a complex ion with a transition metal? a) Cl- b) NCl3 c) PCl3 d) CH4 Answer: d) CH4 because...

For each of the following, identify the lewis acid and the Lewis base:

For each of the following, identify the lewis acid and the Lewis base: a) 4NH3 + Zn2+ --> [Zn[NH3)4]2+ b) 2Cl- + BeCl2 --> [BeCl4]2- c) Mg2+...

How can all Bronsted-Lowry acid-base reactions be classified under Lewis, but Lewis cannot be classified under Bronsted Lowry?

How can all Bronsted-Lowry acid-base reactions be classified under Lewis, but Lewis cannot be classified under Bronsted Lowry? Answer: All Bronsted-Lowry...