This Subatomic Particle determines the atomic number of an element, while the outer-shell electrons determine its chemical reactivity.
Protons (atomic number) and valence electrons (reactivity)
Write the chemical formula for Sodium chloride and the name for MgBr2
NaCl and Magnesium bromide
Identify the reaction type for: 2Mg + O2 --> 2MgO and CH4 + 2O2 --> CO2 + 2H2O
Synthesis and Complete Combustion
What ion is released in solution that causes a substance to be acidic, and what ion is released that causes a substance to be basic?
Hydrogen ions (H+) for acids and Hydroxide ions (OH-) for bases
List four key observation signs that indicate a chemical change (chemical reaction) has taken place in a laboratory.
Color change
Formation of a gas (bubbles)
Formation of a precipitate (solid)
Change in temperature / light emitted (energy change)
Change in odor
State two physical or chemical properties that distinguish metals from non-metals.
Metals: Good conductors, malleable/ductile, lustrous, tend to lose electrons to form cations.
Non-metals: Poor conductors (insulators), brittle, dull, tend to gain/share electrons to form anions. (Any two valid comparisons).
Write the correct chemical formula for Dinitrogen tetroxide and the name for PCl3
N2O4 and Phosphorus trichloride
Balance the following chemical equation:
4Fe + 3O2 --> 2Fe2O3
Black coffee has a pH of 5 and lemon juice has a pH of 2. How many times more acidic is lemon juice compared to coffee?
1,000 times (103) more acidic
Compare pure ionic and molecular compounds based on melting point, water solubility, and electrical conductivity when dissolved in water.
Ionic: High melting points, generally high solubility in water, conducts electricity in water.
Molecular/Covalent: Low melting points, variable/low solubility, does NOT conduct electricity in solution.
Explain what types of elements combine to form ionic compounds versus covalent compounds, and what holds each compound together.
Ionic: Formed between a metal and a non-metal; held together by electrostatic attraction (transfer of electrons).
Covalent: Formed between two non-metals; held together by shared pairs of electrons.
Write the chemical formulas for Calcium nitrate and Aluminum hydroxide
Ca(NO3)2 and Al(OH)3
Translate this word equation into a balanced chemical equation: Hydrogen peroxide (H2O2) liquid decomposes to form liquid water and oxygen gas. Include states!
2H2O2 (l) --> 2H2O (l) + O2 (g)
Describe the color change of Red Litmus, Blue Litmus, and Phenolphthalein when placed in a basic solution like sodium hydroxide (NaOH)
Red Litmus: Turns Blue
Blue Litmus: Stays Blue
Phenolphthalein: Turns Pink / Magenta
Define corrosion, name the key reactants required for the rusting of iron, and give one chemical method used to prevent it.
Definition: The breakdown/deterioration of a metal due to chemical reactions with its environment.
Reactants for Rusting: Iron, Oxygen (O2), and Water (H2O).
Prevention: Galvanization (zinc coating), painting/plating, or sacrificial anodes (any one).
Describe the step-by-step formation of the ionic compound formed between Aluminum and Sulfur using valence electron counts.
Aluminum has 3 valence electrons (Al3+) and Sulfur has 6 valence electrons (S2-).
Two Aluminum atoms transfer a total of 6 electrons to three Sulfur atoms.
Resulting ions: 2 Al3+ and 3 S2- forming Al2S3 (Aluminum sulfide).
Name the following two ionic compounds containing multivalent metals: Fe2O3 and CuSO4
Iron(III) oxide and Copper(II) sulfate
Balance the following chemical equation and classify its reaction type:
2Al (s) + 3CuSO4 (aq) --> Al2(SO4)3 (aq) + 3Cu (s)
Single Displacement
Write the general word equation for a neutralization reaction, and name the two chemical products formed when Hydrochloric acid (HCl) reacts with Sodium hydroxide (NaOH).
General Equation: Acid + Base --> a Salt + Water
Products: Sodium chloride (NaCl) and Water (H2O)
An unlabeled beaker contains a clear liquid suspected to be basic. Outline a safe 2-step lab procedure using chemical indicators to confirm it is a base, and prove complete neutralization after adding acid. What is the final target pH?
Step 1: Dip red litmus paper into the liquid (turns blue) or add a drop of phenolphthalein (turns pink) to confirm it is a base.
Step 2: Slowly add acid while mixing until phenolphthalein turns clear or neutral litmus turns green / universal indicator reads pH 7.
Target pH: pH 7 (or 6–8 range).
Determine the specific charge on the metal ion in both PtS2 and Zr(NO3)4
Platinum(IV) - Pt4+ and Zirconium(IV) - Zr4+
Write the chemical formula for Chromium(III) carbonate and give the systematic IUPAC name for Pb3(PO4)4
Cr2(CO3)3 and Lead(IV) phosphate
Write the word equation AND balanced chemical equation (including state symbols) for the complete combustion of propane gas (C3H8)
Word Equation: Propane + Oxygen --> Carbon dioxide + Water
Balanced Chemical Equation: C3H8 (g) + 5O2 (g) --> 3CO2 (g) + 4H2O (g)
Write the balanced chemical equation with state symbols when aqueous Hydrochloric acid (HCl) reacts with solid Aluminum hydroxide (Al(OH)3), and state the specific chemical name of the salt produced.
3HCl (aq) + Al(OH)3 (s) --> AlCl3 (aq) + 3H2O (l)
Antacids like Mg(OH)2 are taken to relieve heartburn. Explain the chemical reaction occurring in the stomach, identify the acid involved, and explain why the resulting solution stops heartburn.
Stomach acid is Hydrochloric acid (HCl).
The base (Mg(OH)2) undergoes a neutralization reaction with HCl to produce magnesium chloride (MgCl2) and neutral water (H2O).
Neutralization increases the pH toward neutral (~7), removing the excess corrosive H+ ions that cause burning sensations in the esophagus.