Question 1

Which of the following is a Br∅nsted-Lowry acid?

Accepted Answer

A Brønsted-Lowry acid is a substance that can donate a proton (H⁺). NH₄⁺ can donate a proton to form NH₃, making it a Brønsted-Lowry acid.

Question 2

Determine the concentration of CO₃^2- ions in a 0.18 M H₂CO₃ solution.Carbonic acid is a diprotic acid whose K_a1 = 4.3 × 10^-7 and K_a2 = 5.6 × 10^-11.

Accepted Answer

The answer of Determine the concentration of CO₃^2- ions in...

Question 3

When dissolved in water,which compound is generally considered to be an Arrhenius acid?

Accepted Answer

An Arrhenius acid is a substance that, when dissolved in water, increases the concentration of H+ ions. H₂CO₃ (hydrochloric acid) dissociates into H+ and Cl- ions in water, thus acting as an Arrhenius acid.

Question 4

Which of the following species is amphoteric?

Accepted Answer

HPO₄²⁻ is amphoteric because it can act as both an acid (donating a proton to form PO₄³⁻) and a base (accepting a proton to form H₂PO₄⁻).

Question 5

Which of the following is a Br∅nsted-Lowry base?

Accepted Answer

A Brønsted-Lowry base is a substance that can accept a proton (H+). The correct choice, C (NH3), is a Brønsted-Lowry base because it can accept a proton to form NH4+.

Question 6

Identify the base that is in baking soda.

Accepted Answer

Baking soda is sodium bicarbonate, which is chemically represented as NaHCO3.

Question 7

Which of the following is an Arrhenius acid?

Accepted Answer

An Arrhenius acid is a substance that, when dissolved in water, increases the concentration of H+ ions. HS^+ fits this definition as it can donate a proton (H^+) in solution.

Question 8

Carbon dioxide combines with rainwater to form

Accepted Answer

When carbon dioxide dissolves in rainwater, it forms carbonic acid (H2CO3). This is a weak acid that can further dissociate into bicarbonate (HCO3-) and hydrogen ions (H+), which can contribute to acid rain.

Question 9

The Lewis model describes the transfer of

Accepted Answer

The Lewis model describes the transfer of electron pairs, specifically in the context of chemical bonds. It is also known as the electron dot structure or the Lewis dot diagram.

Question 10

Which Br∅nsted-Lowry acid is NOT considered to be a strong acid in water?

Accepted Answer

HNO₂, also known as nitrous acid, is a weak acid in water. The other three choices, HBr, HBr (hydrobromic acid), and HNO₃ (perchloric acid), are all strong acids in water.

Question 11

Identify the weakest acid.

Accepted Answer

The strength of an acid is reflected by its dissociation constant (Ka) value. Among the given options, HF has the weakest Ka value, indicating its weaker acidic strength. Therefore, the correct choice is A) HF.

Question 12

The stomach excretes ________ to kill microorganisms and to activate enzymes that break down food.

Accepted Answer

The stomach excretes hydrochloric acid (HCl) to kill microorganisms and activate enzymes that break down food. Hydrochloric acid creates an acidic environment in the stomach, with a pH of around 2, which helps to denature proteins and kill bacteria that may be present in the food.

Question 13

Which of the following is an Arrhenius base?

Accepted Answer

An Arrhenius base is defined as a compound that dissociates in water to produce hydroxide ions (OH-) as the sole negative ion. RbOH fits this definition as it produces OH- ions in water. The other compounds listed are not Arrhenius bases.

Question 14

________ is found in carbonated beverages due to the reaction of carbon dioxide with water.

Accepted Answer

Carbon dioxide reacts with water to form carbonic acid (H2CO3), which can further dissociate into hydrogen ions (H+) and bicarbonate ions (HCO3-). Therefore, the chemical formula for carbonic acid is H2CO3 and the chemical formula for bicarbonate ion is HCO3-. Since carbonated beverages contain carbon dioxide, they also contain bicarbonate ions. Option B is the only one that contains the correct chemical formula for bicarbonate ion (HCO3-).

Question 15

A Lewis base

Accepted Answer

A Lewis base is a species that can donate an electron pair. This is the defining characteristic of a Lewis base. Options B, C, D, and E do not accurately describe a Lewis base.

Question 16

Place the following in order of increasing acid strength. HBrO₂ HBrO₃ HBrO HBrO₄

Accepted Answer

Acid strength increases with the number of oxygen atoms. HBrO has the least, followed by HBrO2, HBrO3, and HBrO4 having the most, making them stronger acids in that order.

Question 17

Identify the base that is in Drano.

Accepted Answer

NaOH, or sodium hydroxide, is the base commonly found in drain cleaners like Drano.

Question 18

Identify the strongest acid.

Accepted Answer

Among the given options, the strongest acid is the one that can dissociate the most easily, meaning the bond between the H+ ion and the rest of the molecule is weakest. This is determined by looking at the electronegativities of the atoms in the molecule, with higher electronegativity indicating stronger bonds. Te (Tellurium) has the lowest electronegativity among the options, making the H-Te bond the weakest and thus the easiest to break, making option D the strongest acid.

Question 19

Identify the acid that is in vinegar.

Accepted Answer

The acid present in vinegar is acetic acid, which has the chemical formula CH3COOH. Choice D is the only option that contains this formula. The other options are either not acids or do not contain the correct chemical formula for acetic acid.

Question 20

Identify the acid that is in car batteries.

Accepted Answer

The acid used in car batteries is sulfuric acid, which is represented by the chemical formula H₂SO₄.

Quiz 16: Acids and Bases