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High School Chemistry: Talk Through Atoms, Reactions, and Energy
This course covers a full year of high school chemistry: particle models of matter, atomic structure and electron configuration, the periodic table, ionic and covalent bonding, the structure of solids, reactions and balancing equations, the mole and stoichiometry, solutions and acid-base chemistry, oxidation-reduction, bond energy and calorimetry, electric interactions relevant to chemistry, reaction rates, equilibrium, nuclear processes, and engineering design tied to real-world problems. It follows NGSS high school standards and leaves out organic chemistry, detailed quantum mechanics, and physics beyond what's needed for chemical systems.
Each topic starts from what you already know and moves forward one question at a time. Instead of reading a block of text about, say, why ionic compounds dissolve in water, you get asked to predict what happens to a salt crystal dropped in water, explain your reasoning, and then work through what you missed. The tutor checks that you can both explain an idea in your own words and actually do the calculation or diagram it, then circles back later to see if it stuck.
Who it is for
- Students taking a first high school chemistry course, including those with no prior chemistry background
- Students who understood middle school physical science but want their first chemistry course to build in a logical order
- Parents looking for a structured, standards-aligned chemistry course to supplement or replace classroom instruction
- Teachers wanting a tool for students to practice explaining concepts and working problems, not just reviewing notes
- Students preparing for chemistry topics on standardized science tests who want to work through the reasoning, not just memorize formulas
What you will be able to do
- Explain how atomic structure and electron configuration determine an element's position and behavior on the periodic table
- Predict bond type (ionic, covalent, metallic) and resulting physical properties for a given pair of elements
- Balance chemical equations, identify reaction types, and calculate quantities of reactants and products using moles and molar mass
- Calculate molarity, predict precipitation reactions using solubility rules, and write net ionic equations
- Determine whether a reaction is exothermic or endothermic from bond energies and interpret energy diagrams
- Explain how temperature, concentration, and catalysts affect reaction rate, and how equilibrium shifts under Le Chatelier's principle
A taste of a lesson on Chemical Bonding: Ionic and Covalent
The tutor asks, you answer, and it works from what you actually said. No videos to sit through.
The 20 topics in Chemistry
Each topic builds on the ones before it. The tutor checks what you already know and starts there.
Matter, Particles, and Models
Introduce matter as made of particles too small to see, the idea of a scientific model, and how physical properties and states of matter (solid, liquid, gas) reflect particle motion and attraction. Students should be able to explain why solids hold shape, liquids flow but keep volume, and gases spread out, and why models are simplified and revised with evidence.
Atomic Structure and Electron Configuration
Atoms consist of a dense nucleus of protons and neutrons surrounded by electrons in energy levels (shells) and orbitals. Teach atomic number, mass number, isotopes, ion formation, and how electron configurations fill levels by energy. Real understanding means writing configurations for the first 20 elements and identifying valence (outermost) electrons.
Builds on Matter, Particles, and Models
The Periodic Table and Periodic Trends
The periodic table arranges elements by atomic number so that elements with similar valence electron patterns share properties. Teach groups, periods, metals, nonmetals, metalloids, and trends in atomic radius, ionization energy, and electronegativity, explained by nuclear charge and electron shielding. Students use the table to predict relative properties of unfamiliar elements.
Builds on Atomic Structure and Electron Configuration
Chemical Bonding: Ionic and Covalent
Chemical bonds form as atoms gain, lose, or share valence electrons to achieve stable outer shells (octet rule as a useful guide). Teach ionic bonds from electron transfer and electrostatic attraction between oppositely charged ions, covalent bonds from shared pairs, Lewis structures, and how bond type relates to electronegativity difference and the strength of electrical forces between particles.
Builds on The Periodic Table and Periodic Trends
Bulk Structure of Substances: Ionic, Metallic, and Network Solids
Substances differ at the bulk scale: ionic lattices held by strong electrostatic attraction, metals with a sea of delocalized electrons, and covalent network solids such as diamond and quartz with strong bonds throughout. Teach how each structure type predicts melting point, hardness, electrical conductivity, and solubility, so students can match a bulk property pattern to the strength of electrical forces between particles.
Builds on Chemical Bonding: Ionic and Covalent
Intermolecular Forces and Molecular Substances
Molecular substances are held together by intermolecular forces that are much weaker than covalent bonds: London dispersion forces (present in all molecules, grow with size), dipole-dipole attractions (polar molecules), and hydrogen bonding (H bonded to N, O, or F). Teach how these forces explain trends in boiling point, melting point, and solubility, and plan a simple bulk-scale comparison of substances to infer the relative strength of electrical forces between particles.
Builds on Bulk Structure of Substances: Ionic, Metallic, and Network Solids
Chemical Reactions, Balancing, and Conservation of Atoms
A chemical reaction rearranges atoms into new substances. Teach writing and balancing chemical equations, reaction types (synthesis, decomposition, single and double replacement, combustion), and the law of conservation of mass expressed through atom counts. Students show with atom counts and total mass before and after that atoms and mass are conserved in a reaction.
Builds on Chemical Bonding: Ionic and Covalent
The Mole, Molar Mass, and Stoichiometry
The mole is a counting unit (6.022 x 10^23 particles) that links atoms to measurable mass. Teach molar mass from the periodic table, converting between grams, moles, and particles, and using mole-to-mole ratios from balanced equations to calculate reactant and product masses. Real understanding means showing mass and atoms are conserved quantitatively, e.g., predicting grams of product from grams of reactant.
Builds on Chemical Reactions, Balancing, and Conservation of Atoms
Aqueous Solutions, Solubility, Acids and Bases
Ionic compounds dissolve in water as separated ions; soluble and insoluble salts are predicted with solubility rules. Teach molarity, electrolytes, precipitation reactions, net ionic equations for double replacement reactions, and acids and bases with pH as a measure of hydrogen ion concentration, including neutralization. Students explain double replacement outcomes with solubility rules and net ionic reasoning.
Builds on Bulk Structure of Substances: Ionic, Metallic, and Network Solids, The Mole, Molar Mass, and Stoichiometry
Predicting Reaction Outcomes from Electron States and Periodic Trends
Use valence electron configurations, periodic trends, and known chemical property patterns (alkali metals with water, halogen displacement, oxygen combining with metals and nonmetals) to predict and construct explanations for the products of simple reactions, and revise explanations when evidence does not match.
Builds on The Periodic Table and Periodic Trends, Chemical Reactions, Balancing, and Conservation of Atoms
Oxidation-Reduction and Electron Transfer
Oxidation-reduction reactions transfer electrons: oxidation is loss of electrons and reduction is gain, with oxidation numbers used to track transfer. Teach identifying oxidized and reduced species in displacement, combustion, and metal-with-acid reactions, and the basic idea of a galvanic cell in which electron flow through an external circuit releases energy, plus electrolysis as the reverse process driven by electrical energy.
Builds on Chemical Bonding: Ionic and Covalent, Predicting Reaction Outcomes from Electron States and Periodic Trends
Energy in Chemical Reactions: Exothermic, Endothermic, and Energy Diagrams
Chemical reactions absorb or release energy because breaking bonds requires energy input and forming bonds releases energy. Teach endothermic and exothermic reactions, enthalpy change as energy in minus energy out, and the reaction energy diagram showing activation energy and net energy change. Students describe qualitatively how net energy change depends on the balance of bonds broken and formed.
Builds on Bulk Structure of Substances: Ionic, Metallic, and Network Solids, Chemical Reactions, Balancing, and Conservation of Atoms
Calculating Reaction Energy from Bond Energies
Approximate the enthalpy change of a reaction as total bond energy broken minus total bond energy formed, using tabulated bond energies and balanced equations. Students build a model of a reaction in which the net energy change depends on the change in total bond energy, and check it against measured or tabulated values.
Builds on The Mole, Molar Mass, and Stoichiometry, Energy in Chemical Reactions: Exothermic, Endothermic, and Energy Diagrams
Energy Conservation, Thermal Transfer, and Calorimetry
Energy is conserved within a closed system and moves from hotter to colder components until temperatures become uniform. Teach kinetic and potential energy at the particle and macroscopic scales, temperature as average kinetic energy, heat transfer, specific heat, and the equation q = mcΔT. Students plan and conduct a calorimetry-style investigation showing thermal energy redistributes until equilibrium temperature is reached, and compute the energy change of one component from the others.
Builds on Matter, Particles, and Models, Calculating Reaction Energy from Bond Energies
Electric Fields, Forces, and Energy Interactions
Two charged objects or magnets interact through fields, producing forces and changing the potential energy of the system. Teach Coulomb's law qualitatively and quantitatively, electric potential energy depending on charge and separation, and how this interaction energy underlies bond energies and ionic attraction. Students develop a model of two interacting objects showing force and energy changes.
Builds on Chemical Bonding: Ionic and Covalent, Intermolecular Forces and Molecular Substances, Energy Conservation, Thermal Transfer, and Calorimetry
Energy Conversion and Engineering Device Design
Energy can change form (chemical, electrical, thermal, mechanical, radiant) and devices such as batteries, electrolytic cells, and fuel cells convert one form to another under constraints. Teach energy conversion efficiency and energy accounting, then have students design, build, and refine a device converting one form into another within given constraints such as cost and safety.
Builds on Oxidation-Reduction and Electron Transfer, Electric Fields, Forces, and Energy Interactions
Reaction Rates and Collision Theory
Reaction rate depends on how often and how energetically reacting particles collide. Teach collision theory, activation energy, and how increasing temperature or concentration of reactants raises the rate, using particle-level explanations and experimental evidence from rate data. Students apply these principles to explain observed rate changes.
Builds on Matter, Particles, and Models, Energy in Chemical Reactions: Exothermic, Endothermic, and Energy Diagrams
Chemical Equilibrium and Le Chatelier's Principle
Reversible reactions reach dynamic equilibrium when forward and reverse rates are equal and concentrations stop changing. Teach the equilibrium expression, how Le Chatelier's principle predicts shifts when concentration, temperature, or pressure change, and how to specify a change in conditions that increases product yield. Students refine a chemical system design accordingly.
Builds on Predicting Reaction Outcomes from Electron States and Periodic Trends, Reaction Rates and Collision Theory
Nuclear Processes: Decay, Fission, and Fusion
Nuclear reactions change the nucleus itself, unlike chemical reactions. Teach alpha, beta, and gamma decay, changes in proton and neutron numbers, half-life, fission of heavy nuclei, fusion of light nuclei, and the much larger energy released per reaction (mass defect and E=mc^2 at a conceptual level). Students build models showing nuclear composition changes and energy release.
Builds on Atomic Structure and Electron Configuration, Energy in Chemical Reactions: Exothermic, Endothermic, and Energy Diagrams
Engineering Design: Global Challenges and Chemical Solutions
Engineering design begins by analyzing a major global challenge (such as clean water, energy supply, or food production) to specify qualitative and quantitative criteria and constraints that reflect societal needs. Students break a complex problem into smaller solvable subproblems, evaluate candidate solutions against prioritized criteria and trade-offs (cost, safety, reliability, aesthetics, social, cultural, environmental impact), and use a computer simulation to model how proposed solutions affect interacting systems.
Builds on Aqueous Solutions, Solubility, Acids and Bases, Energy Conversion and Engineering Device Design, Chemical Equilibrium and Le Chatelier's Principle, Nuclear Processes: Decay, Fission, and Fusion
Practice questions in Chemistry
A few of the kinds of questions you will work through, with answers.
An atom has 17 protons and 18 neutrons. What is its mass number, and is it a neutral atom or an ion if it has 17 electrons?
See the answer
Mass number 35; it is a neutral atom.
Mass number is protons plus neutrons (17 + 18 = 35); with 17 electrons equal to 17 protons, the charges balance so it's neutral.
Which has a larger atomic radius: potassium (K) or calcium (Ca)?
See the answer
Potassium
Atomic radius decreases left to right across a period because increasing nuclear charge pulls electrons in closer, and K is to the left of Ca in the same period.
Balance this equation: __ Fe + __ O2 -> __ Fe2O3
See the answer
4 Fe + 3 O2 -> 2 Fe2O3
Balancing gives 8 Fe and 6 O atoms on each side, conserving every atom.
How many moles of CO2 are produced from 2.0 moles of C3H8 in the reaction C3H8 + 5 O2 -> 3 CO2 + 4 H2O?
See the answer
6.0 moles of CO2
The mole ratio of C3H8 to CO2 is 1:3, so 2.0 moles of C3H8 produces 2.0 x 3 = 6.0 moles of CO2.
You mix solutions of NaCl and AgNO3. Using solubility rules, will a precipitate form, and if so what is it?
See the answer
Yes, AgCl precipitates.
Silver chloride is insoluble according to solubility rules, while NaNO3 remains dissolved, so AgCl forms as a solid precipitate.
For the equilibrium N2(g) + 3 H2(g) ⇌ 2 NH3(g), which direction does the equilibrium shift if you increase the pressure by decreasing volume?
See the answer
Shifts toward NH3 (the product side)
Decreasing volume favors the side with fewer gas molecules; there are 4 moles of gas on the reactant side and 2 on the product side, so the system shifts to reduce moles of gas.
Questions about this subject
Does this course require a prior chemistry class?
No. It assumes middle school physical science (basic atoms and molecules, states of matter) and algebra with ratios and scientific notation, but no previous chemistry course.
Does this cover organic chemistry or quantum mechanics?
No. The course covers general high school chemistry topics through NGSS standards; organic chemistry, detailed quantum mechanics, and physics beyond chemical-system energy interactions are excluded.
How much math is involved?
You'll need algebra, ratios, and scientific notation for stoichiometry, molarity, and bond energy calculations, but no calculus or advanced math.
Is lab work included?
This is a conceptual and problem-solving course delivered through dialogue, not a lab course, though calorimetry and reaction-rate topics are framed around experimental data and designing investigations.
How does the tutor handle a wrong answer?
The tutor responds to what you actually said, points to the specific gap, and asks a follow-up question that leads you back toward the correct reasoning rather than just giving the answer.