AP Chemistry · Topic 4.2
Net Ionic Equations Practice
Part of Chemical Reactions.(TRA-1.B)
Practice questions
7
Sample questions
5 of 7 — sign in to practice the rest with adaptive difficulty and mastery tracking.
Sample 1difficulty 1/5
Aqueous Pb(NO3)2 is mixed with aqueous KI to form a yellow precipitate; the spectator ions K+ and NO3- are highlighted.
The correct net ionic equation is:
- A
Pb(NO3)2 + 2 KI -> PbI2 + 2 KNO3
- Bcheck_circle
Pb2+(aq) + 2 I-(aq) -> PbI2(s)
- C
Pb2+ + I- -> PbI
- D
K+ + NO3- -> KNO3
Why
Removing K+ and NO3- spectator ions leaves the species that actually combine: Pb2+ and 2 I- forming PbI2(s).
- A
Sample 2difficulty 2/5
Spectator ions are
- A
Always Group 1 metals
- B
The precipitate
- C
Ions that participate in the chemical change
- Dcheck_circle
Ions that appear unchanged on both sides of the equation
Why
Spectator ions don't participate; net ionic equations omit them.
- A
Sample 3difficulty 3/5
Mixing solutions of Pb(NO₃)₂ and KI produces a yellow precipitate. The net ionic equation is
- A
K⁺ + NO₃⁻ → KNO₃
- B
All ions react
- Ccheck_circle
Pb²⁺ + 2 I⁻ → PbI₂(s)
- D
Pb(NO₃)₂ + 2 KI → PbI₂ + 2 KNO₃
Why
K⁺ and NO₃⁻ are spectators. PbI₂ is the bright yellow precipitate ("golden rain" demo).
- A
Sample 4difficulty 3/5
Solid calcium carbonate is dissolved in dilute hydrochloric acid; CO2 effervesces.
The net ionic equation is:
- Acheck_circle
CaCO3(s) + 2 H+(aq) -> Ca2+(aq) + H2O(l) + CO2(g)
- B
Cl- + H+ -> HCl
- C
H+ + OH- -> H2O
- D
Ca2+ + CO3 2- -> CaCO3
Why
Spectator Cl- cancels. Insoluble CaCO3 is written as a unit; H+ reacts with carbonate to liberate CO2 and water, with Ca2+ entering solution.
- A
Sample 5difficulty 3/5
For 2 NaOH + H₂SO₄ → Na₂SO₄ + 2 H₂O, the net ionic equation is
- Acheck_circle
OH⁻ + H⁺ → H₂O (with appropriate coefficients)
- B
No reaction
- C
NaOH + H₂SO₄ → Na₂SO₄ + H₂O
- D
Na⁺ + SO₄²⁻ → Na₂SO₄
Why
Strong acid + strong base. Spectators (Na⁺, SO₄²⁻) cancel.
- A