Chemical reactivity, acids -> bases scale

Chemistry level 2 four credits, question two and beyond

HCl → H+ + Cl-

STRONG ACID

HNO3 → H+ +NO3-

STRONG ACID

H2SO4 → 2H+ SO4^2-

STRONG ACID

what are the three elements of a strong acid

• Complete Dissociation: Strong acids break apart completely in water, releasing all available hydrogen ions (H⁺).

  • Example: HCl → H⁺ + Cl⁻

• High Conductivity: Because they produce many ions, strong acids conduct electricity well.

• Low pH: Strong acids have very low pH values (typically below 3) due to high H⁺ concentration.

CH3COOH (ethanoic acid)

WEAK ACID

H2CO3 (carbonic acid)

WEAK ACID

H3PO4

WEAK ACID

what are the two elements that are important about weak acids?

• Partial Ionization: Weak acids do not fully dissociate in water. Only a small fraction of the acid molecules release hydrogen ions (H⁺).

• Equilibrium: The reaction is reversible, and an equilibrium is established between the undissociated acid and its ions.

NH4CL

ACIDIC SALT

NaHSO4

ACIDIC SALT

NH4NO3

ACIDIC SALT

what are the two elements that are important about acidic salts?

WHAT ARE THEY: Acidic salts form from strong acids and weak bases, and they can lower the pH of a solution due to hydrolysis of acidic ions like NH₄⁺ or HSO₄⁻

FORM: These salts typically form from the reaction of a strong acid with a weak base, or from partial neutralization of a diprotic acid.

what is hydrolysis

Acidic ions react with water to produce H₃O⁺, lowering the pH.

Na2CO3 (NaOH + H2CO3)

BASIC SALT

NaHCO3

BASIC SALT

K2CO3 (KOH + H2CO3)

BASIC SALT

what are the two important facts about basic salts

1. Basic salts are ionic compounds that produce a solution with a pH greater than 7 when dissolved in water.

2. one of the ions reacts with water to produce hydroxide ions (OH⁻), making the solution alkaline.

NH3

WEAK BASE

CO3²-

WEAK BASE

HCO3

WEAK BASE

CH3COO-

WEAK BASE

What are the two elements that are important to know about weak bases

• Partial Proton Acceptance: Weak bases do not fully dissociate in water to accept protons (H⁺). Instead, they establish a reversible equilibrium.

• Equilibrium Behavior: The reaction does not go to completion, meaning only a small amount of OH⁻ is produced.

NaOH

STRONG BASE

KOH

STRONG BASE

important knowledge about strong bases (four)

• Complete Dissociation: Strong bases break apart entirely in water, releasing all their OH⁻ ions.

• No Equilibrium: Unlike weak bases, strong bases do not establish a reversible reaction with water — the dissociation goes to completion.

• Conductivity: They conduct electricity very well because of the abundance of free ions.

• Reaction Rates: Strong bases react quickly with acids, making them ideal for neutralization and titration.

What conducts electricity well, and why?

Strong acids, strong bases because strong acids Produce many H⁺ and anions → lots of free-moving ions and strong bases produce many OH⁻ and cations → strong ionic flow (DUE TO COMPLETE IONIZATION)

What conducts electricity moderately well, and why?

Acidic and basic salts due to Some ionization + hydrolysis → moderate ion presence but vary depending on their ions

what doesn’t conduct electricity very well and why?

Weak acids and weak bases: weak acids because Fewer H⁺ ions → fewer charge carriers and weak bases because Limited OH⁻ production → weaker conductivity (PARTIAL IONIZATION/DISSOCIATION)