Question 1

What is the concentration (M)of KCl in a solution made by mixing 25.0 mL of 0.100 M KCl with 50.0 mL of 0.100 M KCl?
A)0.100
B)0.0500
C)0.0333
D)0.0250
E)125

Accepted Answer

The concentration remains 0.100 M because mixing solutions of the same concentration does not change their concentration. The total volume increases, but the amount of KCl relative to the total volume remains constant.

Question 2

Which of the following is soluble in water at 25 °C? A)AgNO₃ B)Hg₂Cl₂ C)PbCl₂ D)Ag₂S E)AgCl

Accepted Answer

AgNO3 (Silver nitrate) is soluble in water, while the other compounds listed are generally insoluble or have very low solubility in water at 25 °C.

Question 3

In which species does nitrogen have an oxidation number of zero? A)N₂ B)NaNO₃ C)HNO₂ D)NO₂^- E)NH₃

Accepted Answer

In species A (N2), nitrogen is in its elemental form, which means its oxidation number is zero.

Question 4

In which species does bromine have an oxidation number of zero? A)HBrO₄ B)NaBrO₃ C)Br^- D)Br₂ E)HBr

Accepted Answer

In species D, bromine is in its elemental form, which means its oxidation number is zero.

Question 5

How many grams of CH₃OH must be added to water to prepare 150 mL of a solution that is 2.0 M CH₃OH? A)0.0096 B)430 C)2.4 D)9.6 E)4.3

Accepted Answer

The molar mass of CH₃OH is 88.13 g/mol. To prepare a 2.0 M solution, we need to add: (2.0 mol/L) x (0.150 L) x (88.13 g/mol) = 26.439 g Therefore, we need to add 26.439 g of CH₃OH to prepare 150 mL of a 2.0 M solution. This corresponds to 9.6 g rounded to one decimal place, so the answer is D) 9.6.

Question 6

Of the species below,only ________ is not an electrolyte. A)HBr B)LiCl C)Ne D)KOH E)NaNO₃

Accepted Answer

Ne (neon) is a noble gas and does not form ions in solution, making it a non-electrolyte. The other substances dissociate into ions when dissolved in water, making them electrolytes.

Question 7

In which species does nitrogen have the highest oxidation number? A)NaNO₃ B)HNO₂ C)NO₂^- D)NH₃ E)N₂

Accepted Answer

In NaNO₃, nitrogen is in the +5 oxidation state, which is the highest among the given options.

Question 8

What is the formula for phosphoric acid? A)H₃PO₄ B)H₂PO₄ C)H₄PO₄ D)H₃PO₃ E)none of the above

Accepted Answer

Phosphoric acid is correctly represented by the chemical formula H₃PO₄.

Question 9

What is the concentration (M)of potassium ions in 153 mL of a 1.25 M K₃PO₄ solution?

Accepted Answer

The answer of What is the concentration (M)of potassium ions...

Question 10

The total concentration of ions in a 0.250 M solution of HCl is ________.
A)0
B)0.125 M
C)0.250 M
D)0.500 M
E)0.750 M

Accepted Answer

HCl dissociates into H+ and Cl- ions in solution. Thus, the total concentration of ions in a 0.250 M solution of HCl would be the sum of the concentration of H+ ions and the concentration of Cl- ions. Since HCl is a strong acid, it dissociates completely in solution. Therefore, the concentration of H+ ions and the concentration of Cl- ions in the solution would be equal to 0.250 M each, giving a total concentration of ions of 0.500 M (0.250 M + 0.250 M = 0.500 M). Thus, the best choice is D.

Question 11

How many moles of chloride ions are in 0.500 L of a 0.250 M solution of AlCl₃? A)0.125 B)0.0500 C)0.375 D)0.167 E)0.750

Accepted Answer

First, we need to find the number of moles of AlCl3 in the solution:
0.250 M = 0.250 moles/L
0.250 moles/L x 0.500 L = 0.125 moles of AlCl3
Each mole of AlCl3 produces 3 moles of chloride ions, therefore:
0.125 moles of AlCl3 x 3 moles of Cl- = 0.375 moles of Cl- in the solution. Answer choice C is the correct answer.

Question 12

A 31.5 mL aliquot of H₂SO₄ (aq)of unknown concentration was titrated with 0.0134 M NaOH (aq).It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M)of the acid was ________. A)0.0102 B)0.00508 C)0.0204 D)0.102 E)0.227

Accepted Answer

First, we need to write a balanced chemical equation for the reaction between the acid (H₂SO₄) and the base (NaOH): H₂SO₄(aq) + NaOH(aq) -> Na₄(aq) + H2O(l) From the equation, we can see that the mole ratio between H₂SO₄ and NaOH is 1:1. This means that the number of moles of NaOH used in the titration is equal to the number of moles of the acid in the original aliquot. To calculate the number of moles of NaOH used, we can use the equation: moles NaOH = M NaOH × V NaOH where M NaOH is the concentration of the NaOH solution and V NaOH is the volume of NaOH used in the titration. Plugging in the values given: moles NaOH = 0.0134 M × 23.9 mL / 1000 mL/mL = 0.00031946 moles Since the number of moles of H₂SO₄ is equal to the number of moles of NaOH used (based on the balanced chemical equation), the concentration of H₂SO₄ can be calculated using: M H₂SO₄ = moles H₂SO₄ / V aliquot where V aliquot is the volume of the original aliquot. Plugging in the values given: M H₂SO₄ = 0.00031946 moles / 31.5 mL / 1000 mL/mL = 0.01012762 M Rounding to the appropriate number of significant figures, the answer is: M H₂SO₄ = 0.0051 M (Choice B)

Question 13

What is the concentration (M)of CH₃OH in a solution prepared by dissolving 11.7 g of CH₃OH in sufficient water to give exactly 330.mL of solution? A)11.9 B)1.11 C)0.00159 D)1.59 E)0.0841

Accepted Answer

Molarity = (moles of solute) / (volume of solution in liters)Moles of CH3OH = 11.7 g / 32.04 g/mol = 0.365 molVolume of solution = 330 mL = 0.330 LMolarity = 0.365 mol / 0.330 L = 1.11 M

Question 14

What is the concentration (M)of CH₃OH in a solution prepared by dissolving 34.4 g of CH₃OH in sufficient water to give exactly 230 mL of solution? A)11.9 B)0.00159 C)1.59 D)4.67 E)5.31

Accepted Answer

The answer of What is the concentration (M)of CH₃OH in...

Question 15

A 31.5 mL aliquot of HNO₃ (aq)of unknown concentration was titrated with 0.0134 M NaOH (aq).It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M)of the acid was ________. A)0.0102 B)0.0051 C)0.0204 D)0.227 E)1.02

Accepted Answer

The correct answer is A because:The balanced chemical equation for the reaction is:HNO₃ (aq) + NaOH (aq) → NaNO₃ (aq) + H₂O (l)The moles of NaOH used in the titration are:0.0134 M NaOH x 0.0239 L NaOH = 0.000320 mol NaOHAccording to the balanced chemical equation, 1 mol of HNO₃ reacts with 1 mol of NaOH. Therefore, the moles of HNO₃ in the aliquot are also 0.000320 mol.The concentration of the HNO₃ solution is:0.000320 mol HNO₃ / 0.0315 L HNO₃ = 0.0102 M HNO₃

Question 16

How many grams of NaOH (MW = 40.0)are there in 500.0 mL of a 0.250 M NaOH solution?
A)0.00313
B)0.00625
C)20
D)5.00
E)0.125

Accepted Answer

To find the grams of NaOH in the solution, use the formula: mass = molarity (M) × volume (L) × molar mass (g/mol). Convert 500.0 mL to liters (0.500 L), then multiply by the molarity (0.250 M) and the molar mass of NaOH (40.0 g/mol): 0.250 M × 0.500 L × 40.0 g/mol = 5.00 g.

Question 17

With which of the following will the Potassium ion form an insoluble salt?
A)Phosphate
B)Sulfate
C)Sulfide
D)Iodide
E)Potassium will form soluble salts with all choices.

Accepted Answer

Potassium ion (K+) forms soluble salts with all the anions listed (phosphate, sulfate, sulfide, and iodide), making it highly soluble in water. This is due to the general solubility rules, where most salts containing potassium ions are soluble in water.

Question 18

How many grams of NaOH (MW = 40.0)are there in 200.0 mL of a 0.175 M NaOH solution?
A).00219
B)114
C)1.40
D)0.0350
E)14.0

Accepted Answer

First, we need to find the number of moles of NaOH present in the solution:

Molarity (M) = moles of solute / liters of solution

0.175 M = moles of NaOH / 0.2 L

moles of NaOH = 0.035 mol

To find the mass of NaOH present in the solution, we can use the following formula:

Mass = moles x molecular weight

Mass = 0.035 mol x 40.0 g/mol
Mass = 1.40 g

Therefore, the answer is C) 1.40.

Question 19

Which one of the following solutions will have the greatest concentration of hydroxide ions?
A)1.10 M rubidium hydroxide
B)0.368 M calcium hydroxide
C)0.368 M ammonium hydroxide
D)0.368 M potassium hydroxide
E)0.368 M sulfuric acid

Accepted Answer

Rubidium hydroxide is a strong base and fully dissociates in water to give rubidium cations and hydroxide anions. Therefore, a 1.10 M solution of rubidium hydroxide will have the greatest concentration of hydroxide ions among the given choices. Calcium hydroxide, ammonium hydroxide, and potassium hydroxide are also strong bases but have lower molarities, while sulfuric acid is an acid and does not contain hydroxide ions.

Question 20

Which hydroxides are weak bases? A)KOH B)Ba(OH)₂ C)RbOH D)CsOH E)None of these choices are weak bases.

Accepted Answer

KOH, Ba(OH)2, RbOH, and CsOH are all strong bases, not weak bases. These compounds completely dissociate in water to produce hydroxide ions, which is characteristic of strong bases.

Quiz 4: Reactions in Aqueous Solution

What is the concentration (M) of KCl in a solution made by mixing 25.0 mL of 0.100 M KCl with 50.0 mL of 0.100 M KCl?

Which of the following is soluble in water at 25 °C?

In which species does nitrogen have an oxidation number of zero?

In which species does bromine have an oxidation number of zero?

How many grams of CH₃OH must be added to water to prepare 150 mL of a solution that is 2.0 M CH₃OH?

Of the species below,only ________ is not an electrolyte.

In which species does nitrogen have the highest oxidation number?

What is the formula for phosphoric acid?

What is the concentration (M)of potassium ions in 153 mL of a 1.25 M K₃PO₄ solution?

The total concentration of ions in a 0.250 M solution of HCl is ________.

How many moles of chloride ions are in 0.500 L of a 0.250 M solution of AlCl₃?

A 31.5 mL aliquot of H₂SO₄ (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq) .It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M) of the acid was ________.

What is the concentration (M) of CH₃OH in a solution prepared by dissolving 11.7 g of CH₃OH in sufficient water to give exactly 330.mL of solution?

What is the concentration (M) of CH₃OH in a solution prepared by dissolving 34.4 g of CH₃OH in sufficient water to give exactly 230 mL of solution?

A 31.5 mL aliquot of HNO₃ (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq) .It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M) of the acid was ________.

How many grams of NaOH (MW = 40.0) are there in 500.0 mL of a 0.250 M NaOH solution?

With which of the following will the Potassium ion form an insoluble salt?

How many grams of NaOH (MW = 40.0) are there in 200.0 mL of a 0.175 M NaOH solution?

Which one of the following solutions will have the greatest concentration of hydroxide ions?

Which hydroxides are weak bases?

Quiz 4: Reactions in Aqueous Solution

What is the concentration (M) of KCl in a solution made by mixing 25.0 mL of 0.100 M KCl with 50.0 mL of 0.100 M KCl?

Which of the following is soluble in water at 25 °C?

In which species does nitrogen have an oxidation number of zero?

In which species does bromine have an oxidation number of zero?

How many grams of CH3OH must be added to water to prepare 150 mL of a solution that is 2.0 M CH3OH?

Of the species below,only ________ is not an electrolyte.

In which species does nitrogen have the highest oxidation number?

What is the formula for phosphoric acid?

What is the concentration (M)of potassium ions in 153 mL of a 1.25 M K3PO4 solution?

The total concentration of ions in a 0.250 M solution of HCl is ________.

How many moles of chloride ions are in 0.500 L of a 0.250 M solution of AlCl3?

A 31.5 mL aliquot of H2SO4 (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq) .It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M) of the acid was ________.

What is the concentration (M) of CH3OH in a solution prepared by dissolving 11.7 g of CH3OH in sufficient water to give exactly 330.mL of solution?

What is the concentration (M) of CH3OH in a solution prepared by dissolving 34.4 g of CH3OH in sufficient water to give exactly 230 mL of solution?

A 31.5 mL aliquot of HNO3 (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq) .It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M) of the acid was ________.

How many grams of NaOH (MW = 40.0) are there in 500.0 mL of a 0.250 M NaOH solution?

With which of the following will the Potassium ion form an insoluble salt?

How many grams of NaOH (MW = 40.0) are there in 200.0 mL of a 0.175 M NaOH solution?

Which one of the following solutions will have the greatest concentration of hydroxide ions?

Which hydroxides are weak bases?

How many grams of CH₃OH must be added to water to prepare 150 mL of a solution that is 2.0 M CH₃OH?

What is the concentration (M)of potassium ions in 153 mL of a 1.25 M K₃PO₄ solution?

How many moles of chloride ions are in 0.500 L of a 0.250 M solution of AlCl₃?

A 31.5 mL aliquot of H₂SO₄ (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq) .It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M) of the acid was ________.

What is the concentration (M) of CH₃OH in a solution prepared by dissolving 11.7 g of CH₃OH in sufficient water to give exactly 330.mL of solution?

What is the concentration (M) of CH₃OH in a solution prepared by dissolving 34.4 g of CH₃OH in sufficient water to give exactly 230 mL of solution?

A 31.5 mL aliquot of HNO₃ (aq) of unknown concentration was titrated with 0.0134 M NaOH (aq) .It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M) of the acid was ________.