Question 1

Which of the following is soluble in water at 25°C? A) Fe(NO₃)₂ B) FeS C) Fe(OH)₂ D) Fe₃(PO₄)₂ E) FeCO₃

Accepted Answer

Iron(II) nitrate, Fe(NO3)2, is soluble in water due to the nitrate ion, which generally forms soluble salts.

Question 2

An aliquot (28.7 mL) of a KOH solution required 31.3 mL of 0.118 M HCl for neutralization. What mass (g) of KOH was in the original sample?
A) 1.6
B) 0.21
C) 7.2
D) 0.17
E) 0.42

Accepted Answer

B

Question 3

What mass (g) of potassium chloride is contained in 430 mL of a potassium chloride solution that has a chloride ion concentration of 0.193 M?
A) 12.37
B) 6.19
C) 0.0830
D) 0.0643
E) 0.386

Accepted Answer

- First, we need to find the moles of chloride ions in 430 mL of solution.

Amount of chloride ions = concentration x volume 
Amount of chloride ions = 0.193 mol/L x 0.43 L 
Amount of chloride ions = 0.083

- Potassium chloride, KCl, contains one mole of chloride ions per mole of compound, so the amount of KCl in moles is also 0.083.

- Finally, we can use the molar mass of KCl to convert moles to mass.

mass = moles x molar mass 
mass = 0.083 mol x 74.55 g/mol (molar mass of KCl) 
mass = 6.19 g

Therefore, the mass of potassium chloride in 430 mL of solution is 6.19 g, which corresponds to choice B.

Question 4

Zinc is more active than cobalt and iron but less active than aluminum. Cobalt is more active than nickel but less active than iron. Which of the following correctly lists the elements in order of increasing activity?
A) Ni < Co < Fe < Zn < Al
B) Zn < Al < Co < Ni < Fe
C) Ni < Fe < Co < Zn < Al
D) Fe < Ni < Co < Al < Zn
E) Co < Ni < Fe < Zn < Al

Accepted Answer

The correct order based on the given information is Ni < Co < Fe < Zn < Al.

Question 5

Which combination will produce a precipitate? A) NaOH (aq) and HCl (aq) B) AgNO₃(aq) and Ca(C₂H₃O₂)₂(aq) C) NaC₂H₃O₂(aq) and HCl (aq) D) KOH (aq) and Mg(NO₃)₂(aq) E) NaOH (aq) and HCl (aq).

Accepted Answer

When KOH and Mg(NO₃)₂ are mixed, Mg(OH)₂, an insoluble compound, forms as a precipitate.

Question 6

The net ionic equation for the reaction between aqueous sulfuric acid and aqueous sodium hydroxide is . A) 2H⁺(aq) + SO₄²^-(aq) + 2Na⁺(aq) + 2OH^-(aq) - 2H₂O (l) + 2Na⁺(aq) + SO₄²^-(aq) B) 2H⁺(aq) + 2OH^-(aq) - 2H₂O( l) C) SO₄²^-(aq) + 2Na⁺(aq) - 2Na⁺(aq) + SO₄²^-(aq) D) H⁺(aq) + HSO₄^-(aq) + 2OH^-(aq) - 2H₂O (l) + SO₄²^-(aq) E) H⁺(aq) + HSO₄^-(aq) + 2Na⁺(aq) + 2OH^-(aq) - 2H₂O (l) + 2Na⁺(aq) + SO₄²^-(aq)

Accepted Answer

The net ionic equation only includes the species that actually participate in the reaction, which are the hydrogen ions (H+) and hydroxide ions (OH-) from the sulfuric acid and sodium hydroxide, respectively. These ions combine to form water (H2O), leaving behind the spectator ions, which are the sodium ions (Na+) and sulfate ions (SO42-) that do not change during the reaction. The net ionic equation is written as:
2H+ + 2OH- → 2H2O
Any of the answer choices that include the spectator ions or additional products are incorrect.

Question 7

When aqueous solutions of are mixed, a precipitate forms. A) NaI and KBr B) KOH and Ba(NO₃)₂ C) K₂SO₄and CrCl₃ D) Li₂CO₃and CsI E) NiBr₂and AgNO₃

Accepted Answer

When NiBr₂ and AgNO₃ are mixed, AgBr, an insoluble precipitate, forms.

Question 8

Which solution contains the largest number of moles of chloride ions? A) 4.00 mL of 1.000M NaCl B) 25.00 mL of 0.400M KCl C) 10.0 mL of 0.500M BaCl₂ D) 30.00 mL of 0.100M CaCl₂ E) 7.50 mL of 0.500M FeCl₃

Accepted Answer

The answer of Which solution contains the largest number of...

Question 9

What are the respective concentrations (M) of Fe³⁺and I^-afforded by dissolving 0.200 mol FeI₃in water and diluting to 725 mL? A) 0.276 and 0.276 B) 0.276 and 0.828 C) 0.145 and 0.0483 D) 0.828 and 0.276 E) 0.145 and 0.435

Accepted Answer

The answer of What are the respective concentrations (M) of...

Question 10

What volume (mL) of a concentrated solution of sodium hydroxide (6.00 M) must be diluted to 200. mL to make a 1.50 M solution of sodium hydroxide?
A) 0.800
B) 800
C) 45
D) 50.0
E) 0.05

Accepted Answer

M1V1 = M2V2
V1 = (M2V2)/M1
V1 = (1.50 M x 0.200 L)/(6.00 M)
V1 = 0.05 L = 50.0 mL.

Question 11

The point in a titration at which the indicator changes is called the .
A) endpoint
B) equivalence point
C) indicator point
D) standard point
E) volumetric point

Accepted Answer

The endpoint is the point in a titration at which the indicator changes color, indicating that the reaction is complete. The equivalence point is when the amount of titrant added is stoichiometrically equivalent to the amount of analyte present. The other options (indicator point, standard point, volumetric point) are not commonly used terms in titration.

Question 12

A 36.3 mL aliquot of 0.0529 M H₂SO₄(aq) is to be titrated with 0.0411 M NaOH (aq). What volume (mL) of base will it take to reach the equivalence point? A) 1.92 B) 3.84 C) 93.6 D) 187 E) 46.8

Accepted Answer

The answer of A 36.3 mL aliquot of 0.0529 M...

Question 13

Of the reactions below, only is not spontaneous. A) Mg (s) + 2HCl (aq) - MgCl₂(aq) + H₂(g) B) 2Ni (s) + H₂SO₄(aq) -Ni₂SO₄(aq) + H₂(g) C) 2Ag (s) + 2HNO₃(aq) - 2AgNO₃(aq) + H₂(g) D) Zn (s) + 2HI (aq) - ZnI₂(aq) + H₂(g) E) 2Al (s) + 6HBr (aq) - 2AlBr₃(aq) + 3H₂(g)

Accepted Answer

Silver (Ag) does not react with dilute nitric acid (HNO3) to produce hydrogen gas (H2) because it is less reactive than hydrogen in the electrochemical series.

Question 14

In which reaction does the oxidation number of hydrogen change? A) CaO (s) + H₂O (l) -Ca(OH)₂(s) B) HCl (aq) + NaOH (aq) -NaCl (aq) + H₂O (l) C) 2 Na (s) + 2 H₂O (l) -2 NaOH (aq) + H₂(g) D) 2 HClO₄(aq) + CaCO₃(s) -Ca(ClO₄)₂(aq) + H₂O (l) + CO₂(g) E) SO₂(g) + H₂O (l) -H₂SO₃(aq)

Accepted Answer

In reaction C, hydrogen in water (H2O) has an oxidation number of +1, and in the product hydrogen gas (H2), it has an oxidation number of 0. This indicates a change in the oxidation number of hydrogen.

Question 15

Silver ions can be precipitated from aqueous solutions by the addition of aqueous chloride: Silver chloride is virtually insoluble in water so that the reaction appears to go to completion. How Many grams of solid NaCl must be added to 25.0 mL of 0.366 M AgNO₃solution to completely precipitate the silver? A) 1.57 × 10^-⁴ B) 9.15 × 10^-³ C) 6.39 × 10³ D) 0.157 E) 0.535

Accepted Answer

The answer of Silver ions can be precipitated from aqueous...

Question 16

What volume (mL) of 0.135 M NaOH is required to neutralize 13.7 mL of 0.129 M HCl?
A) 14.3
B) 0.24
C) 0.076
D) 6.55
E) 13.1

Accepted Answer

The answer of What volume (mL) of 0.135 M NaOH...

Question 17

Pure acetic acid (HC₂H₃O₂) is a liquid and is known as glacial acetic acid. Calculate the molarity of a solution prepared by dissolving 10.00 mL of glacial acetic acid at 25°C in sufficient water to give500.0 mL of solution. The density of glacial acetic acid at 25°C is 1.049 g/mL. A) 21.0 B) 0.350 C) 0.0210 D) 1.26 × 10³ E) 3.50 × 10^-⁴

Accepted Answer

First, we need to convert the volume of glacial acetic acid from mL to L:
10.00 mL = 10.00/1000 L = 0.01000 L

Next, we need to calculate the number of moles of glacial acetic acid in this volume, using its density and molar mass:

mass of glacial acetic acid = volume x density = 0.01000 L x 1.049 g/mL = 0.01049 g

molar mass of glacial acetic acid = 60.05 g/mol

number of moles of glacial acetic acid = mass/molar mass = 0.01049 g/60.05 g/mol = 0.0001748 mol

Finally, we can calculate the molarity of the solution using the volume of the solution in L:

molarity = number of moles/volume of solution = 0.0001748 mol/0.5000 L = 0.3496 M

The answer should be rounded to three significant figures, giving:

Answer: B) 0.350

The other answer choices are either too high (A, D, and E) or too low (C) and do not reflect the correct molarity of the solution.

Question 18

Which of the following is an oxidation- reduction reaction? A) Cu (s) + 2AgNO₃(aq) - 2Ag (s) + Cu(NO₃)₂(aq) B) Ba(C₂H₃O₂)₂(aq) + Na₂SO₄(aq) - BaSO₄(s) + 2NaC₂H₃O₂(aq) C) HCl (aq) + NaOH (aq) -H₂O (l) + NaCl (aq) D) AgNO₃(aq) + HCl (aq) - AgCl (s) + HNO₃(aq) E) H₂CO₃(aq) + Ca(NO₃)₂(aq) - 2HNO₃(aq) + CaCO₃(s)

Accepted Answer

This is an oxidation-reduction reaction because copper goes from being uncharged (in its elemental form) to having a positive charge (in the compound Cu(NO₃)₂(aq)), which means it lost electrons and was oxidized. Meanwhile, silver goes from having a positive charge (in the compound AgNO₃(aq)) to being uncharged (as a solid), meaning it gained electrons and was reduced.

Question 19

The balanced molecular equation for complete neutralization of H₂SO₄by KOH in aqueous solution is _ . A) H₂SO₄(aq) + 2KOH (aq) - 2H₂O (l) + K₂SO₄(aq) B) 2H⁺(aq) + 2KOH (aq) - 2H₂O (l) + 2K⁺(aq) C) H₂SO₄(aq) + 2OH^-(aq) - 2H₂O (l) + SO₄²^-(aq) D) 2H⁺(aq) + 2OH^-(aq) - 2H₂O (l) E) H₂SO₄(aq) + 2KOH (aq) - 2H₂O (l) + K₂SO₄(s)

Accepted Answer

The equation shows the reactants and products in balanced molecular form, and includes the correct stoichiometric coefficients for the neutralization reaction between the acid H₂SO₄ and the base KOH.

Question 20

What volume (L) of 0.250 M HNO₃is required to neutralize a solution prepared by dissolving 17.5 g of NaOH in 350 mL of water? A) 1.75 B) 0.070 C) 1.75 × 10^-³ D) 50.0 E) 0.44

Accepted Answer

To find the volume of HNO3 needed, first calculate the moles of NaOH: 17.5 g NaOH / 40.00 g/mol = 0.4375 mol. Since the reaction is 1:1, 0.4375 mol of HNO3 is needed. Using M = mol/L, 0.4375 mol / 0.250 M = 1.75 L.

Quiz 4: Aqueous Reactions and Solution Stoichiometry

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

An aliquot (28.7 mL) of a KOH solution required 31.3 mL of 0.118 M HCl for neutralization. What mass (g) of KOH was in the original sample?

What mass (g) of potassium chloride is contained in 430 mL of a potassium chloride solution that has a chloride ion concentration of 0.193 M?

Zinc is more active than cobalt and iron but less active than aluminum. Cobalt is more active than nickel but less active than iron. Which of the following correctly lists the elements in order of increasing activity?

Which combination will produce a precipitate?

The net ionic equation for the reaction between aqueous sulfuric acid and aqueous sodium hydroxide is .

When aqueous solutions of are mixed, a precipitate forms.

Which solution contains the largest number of moles of chloride ions?

What are the respective concentrations (M) of Fe³⁺and I^-afforded by dissolving 0.200 mol FeI₃in water and diluting to 725 mL?

What volume (mL) of a concentrated solution of sodium hydroxide (6.00 M) must be diluted to 200. mL to make a 1.50 M solution of sodium hydroxide?

The point in a titration at which the indicator changes is called the .

A 36.3 mL aliquot of 0.0529 M H₂SO₄(aq) is to be titrated with 0.0411 M NaOH (aq) . What volume (mL) of base will it take to reach the equivalence point?

Of the reactions below, only is not spontaneous.

In which reaction does the oxidation number of hydrogen change?

What volume (mL) of 0.135 M NaOH is required to neutralize 13.7 mL of 0.129 M HCl?

Pure acetic acid (HC₂H₃O₂) is a liquid and is known as glacial acetic acid. Calculate the molarity of a solution prepared by dissolving 10.00 mL of glacial acetic acid at 25°C in sufficient water to give500.0 mL of solution. The density of glacial acetic acid at 25°C is 1.049 g/mL.

Which of the following is an oxidation- reduction reaction?

The balanced molecular equation for complete neutralization of H₂SO₄by KOH in aqueous solution is _ .

What volume (L) of 0.250 M HNO₃is required to neutralize a solution prepared by dissolving 17.5 g of NaOH in 350 mL of water?