Comprehensive Acid-Base and Solution Chemistry Review for Students

What is the Arrhenius definition of an acid?

An acid is a substance that produces hydronium ion (H3O+) when dissolved in water.

What is the Arrhenius definition of a base?

A base is a substance that produces hydroxide ions (OH-) when dissolved in water.

What is a Brønsted-Lowry acid?

A Brønsted-Lowry acid is any substance that can donate a hydrogen ion (H+) to another molecule or ion.

What is a Brønsted-Lowry base?

A Brønsted-Lowry base is a substance that accepts H+ from an acid.

What are monoprotic, diprotic, and triprotic acids?

Monoprotic acids donate one proton (e.g., HCl), diprotic acids donate two protons (e.g., H2SO4), and triprotic acids donate three protons (e.g., H3PO4).

What is the role of electronegative atoms in acidic hydrogen atoms?

Acidic hydrogen atoms are bonded to electronegative atoms, which influences their ability to donate H+.

What is an acid-base reaction?

An acid-base reaction is one in which a proton (H+) is transferred between a Brønsted-Lowry acid and base.

What are conjugate acid-base pairs?

Conjugate acid-base pairs are pairs of chemical species that differ by one H+ and are found on opposite sides of a chemical reaction.

How do you identify a Brønsted-Lowry acid or base?

A Brønsted-Lowry acid must have a hydrogen to donate, while a Brønsted-Lowry base must have a lone pair of electrons to accept H+.

What defines a strong acid?

A strong acid easily donates protons and is essentially 100% dissociated in water.

What defines a weak acid?

A weak acid donates protons with difficulty and is substantially less than 100% dissociated in water.

What is the relationship between acid strength and base strength?

The stronger the acid, the weaker its conjugate base, and vice versa.

What is the significance of polyprotic acids?

Polyprotic acids undergo stepwise dissociations, with the first dissociation being nearly 100% and subsequent dissociations being less extensive.

What is the pH scale used for?

The pH scale measures the acidity or basicity of an aqueous solution.

What is a buffer solution?

A buffer solution is a solution that resists changes in pH when small amounts of acid or base are added.

What is the role of water in acid-base reactions?

Water can act as both an acid and a base, depending on the substances it reacts with.

How do you determine the direction of an acid-base reaction?

The reaction favors the formation of the weaker acid and base.

What happens in a titration?

In a titration, a solution of known concentration is used to determine the concentration of an unknown solution.

What is the significance of acid dissociation constants (Ka)?

Ka values indicate the strength of an acid in solution; higher Ka values correspond to stronger acids.

What is hydronium ion?

The hydronium ion (H3O+) is formed when an acid reacts with water.

What is the formula for the conjugate acid of the cyanide ion (CN-)?

The conjugate acid of CN- is HCN.

What is the formula for the conjugate base of perchloric acid (HClO4)?

The conjugate base of HClO4 is ClO4-.

What is the effect of electronegativity on acid strength?

Higher electronegativity of the atom bonded to the acidic hydrogen increases acid strength.

What is the significance of reversible acid-base reactions?

Many acid-base reactions are reversible, meaning the products can also act as acids or bases.

What is the role of lone pairs in Brønsted-Lowry bases?

A Brønsted-Lowry base must have a lone pair of electrons to accept H+ from an acid.

What is the general behavior of weak bases in proton transfer?

Weak bases have little affinity for protons and do not easily accept H+.

What is the acid dissociation constant (Ka)?

Ka is the equilibrium constant for the dissociation of a weak acid in water, indicating the strength of the acid.

How does the value of Ka relate to acid strength?

Strong acids have Ka values much greater than 1, while weak acids have Ka values much less than 1.

What happens to Ka values in polyprotic acids?

The donation of each successive H+ becomes more difficult, leading to successively lower Ka values.

What is the ion-product constant for water (Kw)?

Kw = [H3O+][OH-] = 1.00 × 10-14 at 25°C.

What does it mean for a substance to be amphoteric?

An amphoteric substance can react as either an acid or a base.

How does water behave in the presence of a base?

Water donates a proton when in contact with a base.

How does water behave in the presence of an acid?

Water accepts a proton when in contact with an acid.

What are the characteristics of an acidic solution?

An acidic solution has [H3O+] > 10-7 M and [OH-] < 10-7 M.

What are the characteristics of a neutral solution?

A neutral solution has [H3O+] = 10-7 M and [OH-] = 10-7 M.

What are the characteristics of a basic solution?

A basic solution has [H3O+] < 10-7 M and [OH-] > 10-7 M.

What is the formula to calculate pH from [H3O+]?

pH = -log[H3O+].

What is the pH of a solution with [H3O+] = 1 × 10-5 M?

The pH is 5.0.

How do you find [H3O+] from pH?

[H3O+] = 10-pH.

What is the pH of lemon juice with a pH of 2?

[H3O+] = 10-2 = 1 × 10-2 M.

How do you calculate pH from [OH-]?

First find [H3O+] using [H3O+] = Kw/[OH-], then use pH = -log[H3O+].

What is the pH of a 0.01 M solution of HCl?

Since HCl is a strong acid, pH = 2.0.

What is an acid-base indicator?

An acid-base indicator is a dye that changes color depending on the pH of the solution.

What is the significance of the pH scale?

The pH scale indicates the acidity or basicity of a solution, typically ranging from 0 to 14.

What does a change of 1 pH unit represent?

A change of 1 pH unit represents a tenfold change in [H3O+].

What is the relationship between pH and pOH?

pH + pOH = 14.00.

How do you determine if a solution is acidic, neutral, or basic based on pH?

pH < 7 indicates acidic, pH = 7 indicates neutral, and pH > 7 indicates basic.

What is the [H3O+] concentration in a soft drink with a pH of 3.1?

[H3O+] = 10-3.1 M.

What is the significance of significant figures in pH calculations?

An antilogarithm has the same number of significant figures as the original number has to the right of the decimal point.

How do you calculate the pH of a solution with a negative pH value?

Enter the negative pH on a calculator and press 'INV' and 'log' to find [H3O+].

What is the pH of a 0.0045 M solution of HClO4?

pH = 2.35, since HClO4 is a strong acid and fully dissociates.

How do you find the pH of a strong base like NaOH?

Calculate [OH-], then use pH = 14.00 - pOH.

What is the pH of a 0.0032 M solution of NaOH?

pH = 11.51, calculated from pOH = 2.49.

Define one equivalent of an acid.

The amount of an acid that contains 1 mole of H+ ions.

Define one equivalent of a base.

The amount of a base that contains 1 mole of OH- ions.

What is normality (N) in acid-base solutions?

The number of equivalents of acid or base per liter of solution.

How do normality and molarity relate for monoprotic acids?

Normality (N) equals molarity (M) for monoprotic acids.

What is the normality of 1 N H2SO4?

0.5 M H2SO4, as it is diprotic.

How do you calculate equivalents from grams of a diprotic acid?

Convert grams to moles using molar mass, then multiply by 2 for equivalents.

What is the normality of a solution made by diluting 6.5 g of H2SO4 to 200 mL?

0.66 N or 660 mEq/L.

What happens when marble (CaCO3) reacts with hydrochloric acid?

It releases bubbles of CO2.

What is the net ionic equation for the reaction of an acid with a hydroxide ion?

H+(aq) + OH-(aq) → H2O(l).

What do bicarbonate and carbonate ions yield when reacting with an acid?

They yield carbonic acid, which decomposes to CO2 and water.

What is the reaction of acids with ammonia?

Acids react with ammonia to yield water-soluble ammonium salts.

How can you predict if a salt solution will be acidic, basic, or neutral?

Classify salts based on the acid and base they were formed from in a neutralization reaction.

What type of solution does a salt of a strong acid and weak base produce?

An acidic solution, e.g., NH4Cl from HCl and NH3.

What is the concentration of H3O+ in a 0.0045 M HClO4 solution?

[H3O+] = 0.0045 M.

What is the pOH of a 0.0032 M NaOH solution?

pOH = 2.49.

What is the relationship between normality and the number of H+ or OH- ions produced?

Normality = Molarity × number of H+ or OH- ions per formula unit.

What is the molar mass of H2S?

34.0 g/mol.

What is the molar mass of H2SO4?

98.0 g/mol.

What is the significance of the negative logarithm in pH calculations?

It converts the concentration of H3O+ to a pH scale.

What is the formula for calculating pH from [H3O+]?

pH = -log[H3O+].

What does the reaction of acids with carbonate ions produce?

Water and carbon dioxide gas.

What is the role of strong acids in determining pH?

They fully dissociate in solution, providing H3O+ ions directly.

What type of solution does a salt formed from a strong acid and a weak base yield?

An acidic solution.

What is the reaction that occurs when NH4Cl is dissolved in water?

NH4+ (aq) + H2O (l) ⇆ NH3 (aq) + H3O+ (aq)

What type of solution does a salt formed from a weak acid and a strong base yield?

A basic solution.

What is the reaction that occurs when sodium bicarbonate is dissolved in water?

HCO3- (aq) + H2O (l) ⇆ H2CO3 (aq) + OH-(aq)

What type of solution does a salt formed from a strong acid and a strong base yield?

A neutral solution.

What determines the pH of a salt formed from a weak acid and a weak base?

The ion that reacts to the greater extent will govern the pH.

What is the classification of BaCl2 in terms of acidity or basicity?

It gives a neutral solution.

What is the classification of NaCN in terms of acidity or basicity?

It gives a basic solution.

What is the classification of NH4NO3 in terms of acidity or basicity?

It gives an acidic solution.

What is a buffer?

A combination of substances that act together to prevent a drastic change in pH; usually a weak acid and its conjugate base.

What happens to the pH of a buffer solution when OH- is added?

The pH increases only slightly; the acid component of the buffer neutralizes the added OH-.

What happens to the pH of a buffer solution when H+ is added?

The pH decreases only slightly; the base component of the buffer neutralizes the added H+.

What is the Henderson-Hasselbalch equation used for?

To calculate the pH of a buffer solution.

What is the most effective pH range for a buffer dependent on?

The pKa of the acid and the ratio of HA and conjugate base.

What should the ratio of [HA] to A- be for an effective buffer?

It should be close to 1.

What is the relationship between the molar amounts of HA and A- in a buffer and the amounts of acid or base that may be added?

They should be approximately 10 times greater.

What is titration?

A procedure for determining the total acid or base concentration of a solution.

What does the pH of a solution give?

The H3O+ concentration but not necessarily the total acid concentration.

What is the formula used for titration when one mole of acid reacts with one mole of base?

Macid × Vacid = Mbase × Vbase.

What is the formula used for titration when the coefficients for acid and base are not the same?

(Eq)acid = (Eq)base; NACID × Vacid = Nbase × Vbase.

What is the neutralization reaction for acetic acid and NaOH?

CH3CO2H(aq) + NaOH(aq) → H2O(l) + CH3CO2-Na+(aq).

How can the molarity of acetic acid in vinegar be determined?

By using the balanced reaction and titration data.

What is the concentration of acetic acid expressed in milliequivalents?

It is calculated as (0.890 Eq/L)(1000 mEq/1 Eq) = 890 mEq/L.

What happens to the concentration of HF when NaOH is added to the buffer?

The HF concentration decreases as it reacts with the added base.

What is the new concentration of F- after adding NaOH to the buffer?

It increases due to the neutralization reaction.