Metalloids
Lesson notes
Overview
Elements like silicon sit on the staircase between metals and non-metals — the stuff of semiconductors. This topic is rated beginner and is number 11 of 110 in Chemistry. Core ideas and first intuitions. No prior knowledge needed.
What you are seeing
The panel above shows an interactive animation of the idea. Every slider changes one quantity so you can see its effect on the outcome. The animation is drawn live from the model, so everything you see responds to the sliders. Press Space to pause, use Restart to replay from the start, and change the speed to slow down quick events.
In depth
Metalloids such as boron, silicon, germanium and arsenic lie on the diagonal staircase between metals and non-metals and have intermediate properties. They look like metals but are brittle, and their electrical conductivity lies between conductors and insulators, increasing with temperature. This makes them semiconductors, which are the basis of transistors, solar cells and all modern electronics. Adding small amounts of other atoms, doping, adjusts their conductivity precisely.
Reading the relationship
The expression "Si, Ge, As …" is a compact summary of the idea. It uses the symbols S, i, G, e, A, s; name what each one stands for before you start. Then use the sliders to see how changing one quantity changes the others.
A guided exploration
1. Run the animation once with the default settings and describe in words what happens. 2. Change one slider at a time and note which quantity responds most. 3. Push each slider to its extreme and decide whether the result still makes sense.
Try this
Start by only moving one slider at a time. Say aloud what you expect, then check.
Common pitfalls
Keep the particle picture in mind. Mistakes often come from treating a rate, an amount and an equilibrium position as the same thing, or from ignoring units and conditions.
How it connects
It builds on “The Halogens”, the topic before it in Chemistry. Once you are comfortable, continue with “Electronegativity Across a Period”.
Why it matters
Chemistry links the tiny scale of atoms to the materials, medicines and energy we use every day.
Where you might use it
- Revising “Metalloids” before a class, exam or certification
- Predicting how fast a reaction runs in a lab or an industrial plant
- Choosing materials, medicines and fuels based on how their atoms bond and react
- Reading the labels and data sheets of cleaning products, batteries and food
Frequently asked questions
What is Metalloids?
Elements like silicon sit on the staircase between metals and non-metals — the stuff of semiconductors. It is a beginner topic in Chemistry.
How do I use the Metalloids simulation?
The panel at the top shows an interactive animation of the idea. Every slider changes one quantity so you can see its effect on the outcome. Move the sliders one at a time, then press Space to pause the animation and look closer.
What does the formula mean?
The expression Si, Ge, As … packs the idea into symbols. Name each symbol first, then change one quantity with the sliders and see which others respond.
Who is this topic for?
Core ideas and first intuitions. No prior knowledge needed. If the quiz feels hard, reread the lesson notes and try the previous topic first.
What should I learn before this?
Start with “The Halogens”, the previous topic in Chemistry. Each topic in a subject builds on the ones before it.
How do I track my progress?
Press “Mark as learned” on this page. Progress is stored only in this browser and is never sent anywhere. The Browse page can show topics you have learned or still need to learn.
Quick quiz
More in Chemistry
See all →Electronegativity Across a Period
Atoms pull harder on shared electrons as you move right across a period.
Atomic Radius Trend
More protons pull the electron cloud tighter, so atoms shrink across a period.
Ionisation Energy Trend
Smaller atoms hold electrons more tightly, so more energy is needed to remove one.