AP Chemistry: Reactions Quiz

What is always soluble with some exceptions? (Name).

Nitrates, Acetates, Group 1 Elements, Ammonium

Sulfates: PMS and Castro Bear

Group 17: PMS

What are the exceptions to solubillity? (Name + Formula).

Lead (Pb²⁺), Mercury (Hg²⁺), and Silver (Ag⁺) are INSOLUBLE with Sulfates and Group 17 elements)

Calcium (Ca²⁺), Strontium (Sr²⁺), Barium (Ba²⁺) and INSOLUBLE with Sulfates

What are the three weak bases?

Sodium Hydroxide (NaOH), Potassium Hydroxide (KOH), Lithium Hydroxide (LiOH).

What are the six strong acids? (Name + Formula).

Hydrochloric Acid (HCl), Sulfuric Acid (H2SO4), Perchloric Acid (HClO4), Nitric Acid (HNO3), Hydroiodic (HI), Hydrobromide (HBr).

What is the Redox Mnemonic?

LEO the lion goes GER

Lose Electrons —> Oxidation

Gain Electrons —> Reduction

What are the 5 oxidation number rules?

1. In elemental form, oxidation number = 0

   1. For example, H₂ , Zn, and S₈ are not chemically bonded to another element so, their oxidation number is zero.

2. In simple ions, the oxidation number = the charge of the ion

   1. For example, Cl^- has an oxidation number of -1

3. In COMPOUNDS ONLY oxygen has an oxidation number of -2

   1. EXCEPTION ONE: If it is in a peroxide (H₂O₂)

   2. EXCEPTION TWO: If it is IN ELEMENTAL FORM, Oxygen is -1

4. When Hydrogen is bonded to nonmetals, the Oxidation number is 1

   1. EXCEPTION ONE: Unless it is ELEMENTAL FORM

   2. EXCEPTION TWO: Unless it is an Anion, like NaH, then Oxidation Number is -1

5. Compounds add up to be zero for neutral ionic (NON POLYATOMIC) and covalent

   1. POLYATOMICS is the overall charge for the ion

Predict the Reaction for this equation: K3PO4 + Ca(NO3)2 →

Molecular: K3PO4 (aq) + Ca(NO3)2 (aq) →KNO3 (aq) + Ca3(PO4)2

Net Ionic: Ca²⁺(aq) + PO4^3-(aq) —> Ca3(PO4)2

Predict the Reaction for this equation and give the justification: HCl + CaCO3 →

Molecular: HCl(aq) + CaCO3(s) → CO2(g) + H2O (liq) + CaCl2 (aq)+

Net Ionic: H⁺(aq) + CaCO3(s) —> CO2 (g) + H2O (liq) + Ca²⁺(aq)

Explanation: This is an acid-carbonate reaction where a SPECIAL double reaction occurs. When the Hydrogen and Carbonate bond, H2CO3 is EXTREMELY unstable so, it splits up into Carbon Dioxide and Water. For the net ionic, when you write out the total ionic, cancel out the spectator ions and you get the net!

HCN + NaOH —>

Molecular: HCN + NaOH —> H2O (liq) + NaCN (aq)

Net Ionic: HCN(aq) + OH^-(aq) —> H2O (liq) + CN^-(aq)

Explanation: This is an acid-base neutralization reaction where sodium is the spectator ion. HCN is a weak acid that doesn’t dissociate, NaOH is a strong base that completely breaks down, H2O doesn’t break down because it is a pure liquid, and CN is all alone without Na :(

Na2S + ZnCl2 →

Molecular: Na2S (aq) + ZnCl2(aq) → 2NaCl2 (aq) +ZnS(s)

Net: S^2-(aq) + Zn²⁺(aq) —> ZnS(s)

Explanation: From the total ionic, we can cross out Sodium and Chloride. Since Zinc and Sulfur form a precipitate, they get to stay!

HBr + NH3 →

Molecular: HBr(aq) + NH3(aq) → NH₄Br(aq)

Net: H⁺(aq) + NH3 (aq) → NH4(aq)

Explanation: Since HBr is a strong acid, it splits into 2 ions, NH3 is a weak base so it stays together, NH4Br is a soluable salt so, it splits into a salt. Bromine is a spectator so it is excluded from the net ionic :(

HClO4 + Mg(OH)2 →

Molecular: HClO4(aq) + Mg(OH)2(s) → 2H2O(liq) + Mg(ClO4)2 (aq)

Net: 2H⁺(aq) + Mg(OH)₂(s) → 2H2O(liq) + Mg²⁺(aq)

Explanation: Since perchloric acid is a strong base, it dissociates, magnesium hydroxide is a solid so it is stays, water is a pure liquid, Magnesium Chloride is a soluble salt so it dissociates.

MgCO3 + HNO3 →

Molecular: MgCO3 (s) + HNO3 (aq) → H2O(liq) + CO2(g) + Mg(NO3)2 (aq)

Net: MgCO3 (s) + H⁺(aq) → CO2 (g) + H2O (liq) + Mg²⁺(aq)

Explanation: Magnesium carbonate is a solid so it doesn’t dissociate, Nitric acid is a strong acid that completely dissociates, Water is a pure liquid, carbon dioxide is a gas, and magnesium nitrate is a soluble salt that completely dissociates! But…Nitrate is left out because its a spectator :(

K2S + H2SO4 →

Molecular: K2S + H2SO4 → H2S + K2SO4

Net: S^2-+2H⁺(aq) → H2S(g)

Explain: Potassium Sulfide is a salt that splits up (their relationship just wasn’t working out… what can I say!), Sulfuric Acid is a strong acid that splits up (idk about strong relationship…), H2S is a gas that stays together (now theres a strong relationship!), Potassium sulfate is a salt that splits up (again, another problem couple…)

SO2 + H2O →

Molecular: SO2 + H2O →H2SO3(aq)

Net Ionic: SO2 + H2O →H2SO3(aq)

Explanation: The net ionic is the same as the molecular formula because the reactants are gasses and liquids!! (talk about strong couples!)

NO2 + H2O →

Molecular: NO2 + H2O → H2NO3 (aq)

Net: NO2 (g) + H2O (liq) → H2NO3 (aq)

Explanation: The net ionic is the same as the molecular formula because the reactants are gasses and liquids!! (talk about strong couples!)

H2O + MgO →

Molecular: H2O + MgO → Mg(OH)2(s)

Net: H2O(liq) + MgO(s) → Mg(OH)2(s)

Explanation: Another case of the strong couples! The liquid water and solid magnesium oxide are just too unbreakable! So, this reaction is a synthesis base formation reaction.

Li2O + H2O →

Molecular: Li2O + H2O → 2Li(OH)

Net: Li2O (s) + H2O (liq) → 2Li(OH)

Explanation: Another case of the strong couples! The liquid water and solid Lithium Oxide are just too unbreakable! So, this reaction is a synthesis base formation reaction.

SrSO3 + HCl →

Molecular: SrSO3 + HCl → SO2 + SrCl2 + H2O

Net: SrSO3(s) + H+(aq) → SO2(g) + Sr2+(aq) + H2O(liq)

Explanation: The solid strontium sulfite is going strong and hasn’t broken up (they are soulmates!!), HCL is a strong acid but is will break up (talk about performative couple…), SO2 is a gas that will stay together forevaa, Strontium Chloride is a salt that will break up saldy, and H2O will go strong as a pure liquid!

HNO3 + K2SO3 →

Molecular: HNO3 + K2SO3 → SO2 + KNO3 + H2O

Net Ionic: 2H⁺(aq) + SO3^-(aq) → SO2 (g) + H2O (liq)

Explanation: Nitric acid is a strong acid but a bad relationship because they broke up, Potassium sulfite is another bad couple since they are ionic, SO2 is a GAS that will never break up (#true love), ALSO water is a pure liquid so, another soulmate!

NH4Br + KOH →

Molecular: NH4Br + KOH → NH3 + H2O + KBr

Net Ionic: NH4 +(aq) + OH-(aq) → NH3(l) + H2O(l)

Explanation: NH4Br, man they broke up :(, Potassium Hydroxide also broke up because their relationship was WEAK, Ammonia and water are the liquids that are #truesoulmates, and KBr is a WEAK COUPLE!!!

What does water always exist as?

a PURE LIQUID!!

What does magnesium always exist as?

A solid/metal!

What does Iron always exist as?

A solid/metal!

What does oxygen always exist as?

as a gas: O2

What does Hydrogen always exist as?

As a gas: H2

What does carbon dioxide (CO2) always exist as?

A gas!

What does Carbon Monoxide exist as?

A Gas!

What does Methane (CH4) exist as?

A gas!

What does Ammonia (NH3) exist as?

A gas! Think of the pungent smell used in fabuloso!

What does Sulfur Dioxide Exist as?

A gas!

What is Propane and what does it exist as?

Propane is C3H8 and exists as a gas!

What does hydrogen peroxide (H2O2) exist as?

As a liquid!

What does ethanol (C2H5OH) exist as?

Ethanol exists as a liquid! Think alcohol as a drink and in hand sanitizer!

What is Isopropyl Alcohol and what does it exist as?

Isopropyl Alcohol (C3H7OH) and it exists as a liquid. Think rubbing alcohol that you use when you get a wound. (ouch!)

What does Acetone exist as and what is it?

Acetone is CH3COCH3 and it is a liquid! Think nail polish remover.

What does Octane exist as and what is it?

Octane is C8H18 and it exists as a liquid.

What is the blueprint for acid formation?

Nonmetal Oxide + Water

CO2 + H2O →H2CO3

What is the blueprint for base formation?

Metal oxide + water

CaO (s) + H2O (liq) →Ca(OH)2 (aq)

What is the blueprint for an acid base reaction?

HX + MOH → MX + H2O

The anions and cations come together and water forms!

What are all four blueprints for Gas-Forming Reactions?

1. Metal Carbonate/Bicarbonate + acid →metal salt + CO2(g) + H2O

   1. Na2CO3(aq) + 2HCl(aq) →2NaCl (aq) + CO2(g) + H2O

2. Metal Sulfide + Acid (STRONG ACID) → Metal Salt + H2S (g)

   1. Na2S(aq) + 2HCl (aq) → 2NaCl(aq) + H2S (g)

3. Metal Sulfite + Acid → Metal Salt + SO2 (g) + H2O (liq)

   1. Na2SO3(aq) + 2HCl (aq) →2NaCl (aq) + SO2(g) + H2O (liq)

4. Ammonium Salt + strong base → metal salt + NH3 (g) + H2O (liq)

   1. NH4Cl (aq) + NaOH (aq) →NaCl (aq) + NH3 (g) + H2O (liq)

Complete the rxn: A solution of calcium chloride is mixed with a solution of sodium fluoride.

Double replacement!

CaCl2 + 2NaF → CaF2 + NaCl

Complete the rxn:Sulfur trioxide gas is bubbled through water.

Acid synthesis reaction!

SO3 (g) + H2O (liq) → H2SO4 (aq)

Complete the rxn:Nitric acid is mixed with sodium hydroxide. 

Acid-base neutralization!

HNO3 (aq) + NaOH(aq)→ H2O(liq) + NaNO3(aq)

Complete the rxn: Solid calcium carbonate is mixed with sulfuric acid.

CaCO3 (s) + H2SO4 (aq) → CaSO4(s) + H2O + CO2

the burp (why am i like this 😭)

Complete the rxn: A solution of sodium sulfide is mixed with a solution of lead II acetate.

NaS (aq) + Pb(C2H3O2)2 → Na(C2H3O2) + PbS (s)

Find the Net Ionic: A solution of sodium sulfite is mixed with hydrochloric acid.

SO3^2-(aq) + 2H+ (aq) →H20 (liq) + SO2 (g)

Find the Net Ionic: Solutions of acetic acid and potassium hydroxide are mixed.

OH-(aq) + HC2H3O2 (aq) → C2H3O2 (aq) + H2O (liq)

Find the Net Ionic: Solutions calcium nitrate and sodium carbonate are mixed.

Ca²⁺(aq) + CO3^2-(aq) → CaCO3 (s)

Find the Net Ionic: Magnesium metal reacts with nitric acid.

Mg(s) + 2H⁺(aq) → Mg²⁺+ H2(g)

Find what is being oxidized/reduced, find the respective agents, and balance it for charge and mass: Ag⁺ + Sn²⁺ → Ag + Sn⁴⁺

Oxidized: Sn²⁺

Reducing Agent: Sn²⁺

Reduced: Ag⁺

Oxidizing Agent: Ag⁺

Balanced Eq: Sn²⁺+2Ag →Sn⁴⁺+2Ag

Find what is being oxidized/reduced, find the respective agents, and write the half rxns: H₂O₂ + Ni²⁺ → Ni³⁺ + H₂O

Oxidized: Ni²⁺

Reducing Agent: Ni²⁺

Reduced: H2O2

Oxidizing Agent: H2O2

Balanced Eq: 2Ni²⁺(aq) + H2O2 (aq) + 2H⁺(aq) → 2H2O (liq) + 2Ni³⁺(aq)