Guides
Chemistry study guides
Free, in-depth guides to studying chemistry with the periodic table - how to read the table, the trends that make it predictable, memorizing the elements efficiently, and the rules of electron configuration.
How to Read the Periodic Table: A Beginner's Guide
Learn to read the periodic table: what each number means, how rows and columns are organised, and why an element's position tells its story.
Periodic Trends Explained Simply
Understand periodic trends the easy way: how atomic radius, ionization energy, and electronegativity change across and down the table, and why.
How to Memorize the Elements (Without Brute Force)
Smart ways to memorize the periodic table elements: what actually needs recall, how to use groups and patterns, and spaced-repetition study techniques.
Electron Configuration Rules Made Clear
A clear guide to electron configuration: the three rules for how electrons fill orbitals, shorthand notation, and reading them off the table.
Chemistry Exam Prep With the Periodic Table
Use the periodic table as your exam toolkit: what to revise, how to read answers off the table under pressure, and the checks that recover easy marks.
Element Groups and Families Explained
Meet the periodic table's families: alkali metals, alkaline earth metals, transition metals, halogens, and noble gases, and why group-mates behave alike.
Metals, Nonmetals, and Metalloids: The Big Divide
The most useful split on the periodic table: how to tell metals, nonmetals, and metalloids apart, where the dividing line runs, and why it matters.
Using Electronegativity to Predict Chemical Bonds
Electronegativity is the number that predicts bond type. Learn to compare values across the table to tell ionic, polar, and covalent bonds apart.
Ionic vs Covalent Bonds Explained
Ionic bonds transfer electrons and covalent bonds share them. Learn to tell the two apart from the periodic table and predict a compound's properties.
How to Write Chemical Formulas
Learn to write correct chemical formulas by balancing ion charges. A step-by-step crossing method for ionic compounds, polyatomic ions, and ratios.
Oxidation States Made Simple
Oxidation states track where electrons go in a compound. Learn the assignment rules, work through examples, and see why they matter for redox and formulas.
Valence Electrons and the Octet Rule
Valence electrons drive chemistry, and the octet rule explains why. Learn to count them from the table and predict how atoms bond to fill their shells.
How to Calculate Molar Mass
Calculate the molar mass of any compound straight from the periodic table, with worked examples and gram-to-mole conversions you can check.
Moles and Avogadro's Number Explained
What a mole really is, why Avogadro's number is exactly 6.02214076 × 10²³, and how to convert between grams, moles and particles with confidence.
Balancing Chemical Equations
A method for balancing chemical equations that always works: adjust coefficients, never subscripts. Worked combustion, synthesis and ionic examples.
Reading Isotopes and Atomic Mass
Mass number, isotopic mass and standard atomic weight are three different things. Learn the difference and calculate a weighted-average atomic mass.