Chem Club Semester Review
A semester review: spreading chemistry through practice, curiosity, and collaboration.
唐泽霖 / Zelin Tang
founderleader
I am Zelin Tang, the founder of this website. In Grade 10, my love for chemistry led me to join the chemistry club. At the end of the second semester of Grade 10, together with three other club members, I began writing and publishing more than ten articles on the "Second High Chem Club" WeChat public account. These articles covered topics such as fun club experiments and the principles behind them, chemistry in everyday life, and popular-science explanations of chemistry knowledge. Moving forward, we will also publish a series of articles on green chemistry and environmental protection on both the website and the public account. Through interesting and thoughtful content, I hope to spark more people's interest in chemistry and help them understand the subject from multiple perspectives.
Contributed Articles
The Final Experiment of 2025: Elephant Toothpaste
Our final experiment of the year: Elephant Toothpaste.
Flame Tests
Why do different metals produce different colors in a flame? This article explains flame tests from the perspective of spectra and energy transitions.
"Heart of the Ocean": Changes in Chromium Oxidation States
"Heart of the Ocean" is a striking color-change experiment. By adding hydrogen peroxide and dilute sulfuric acid to potassium chromate solution, the colors rapidly shift through yellow, orange, blue, and green, revealing chromium in different oxidation states.
"A Garden in Water": Plant-Like Growth in Alkaline Solution
Water gardens are classic chemistry demonstrations in which metal-salt crystals grow into colorful, plant-like branching structures in solution.
The 2025 Nobel Prize in Chemistry
The 2025 Nobel Prize in Chemistry honors breakthroughs related to MOFs. This article introduces the laureates, the science behind metal-organic frameworks, and why these porous materials matter.
Iron's Dual Identity
Is iron more commonly +2 or +3, and why? Starting from electron configuration and Hund’s rule, this article explains the two common oxidation states of iron in chemistry and daily life.
Golden Rain
In this classic experiment, lead ions and iodide ions form bright yellow lead iodide crystals that fall like golden rain. This article explains the phenomenon and the chemistry behind it.
"From Stone to Blue": The Chemistry of Ultramarine
This article explores the chemistry behind ultramarine, the historic blue pigment seen in art, and explains its composition, color, and cultural significance.
Neanderthals and Chemistry
Neanderthals lived in Europe and western Asia tens of thousands of years ago. This article explores the chemistry behind their tools, fire use, and painting materials.
AP Chemistry: Electron Configuration
AP Chemistry: Electron configuration. This article explains how electrons are arranged outside the nucleus, from shells to subshell notation, and why electron configuration matters for understanding atomic structure and chemical behavior.
What Is an Atom? A Journey into the Microscopic World
From Dalton's solid sphere to Thomson's plum-pudding model, Bohr's quantized orbits, and Schrödinger's electron cloud, this article traces how our picture of the atom has been continually rewritten.
Copper Sulfate Roses: Crystal Blossoms from Solution
When crystals grow on roses, ordinary petals turn into dazzling blue blooms. This article introduces the copper sulfate rose experiment and the chemistry of crystal growth.