The idea of electron shells is essential in chemistry and also plays an important part in various areas of physics so needs to be discussed in its own right. But before we look at electron shells let's be clear that this is just a model - a way of imagining what is going on inside … Continue reading Electron Shells
Atoms – basic ideas
The original idea of an atom came from asking a very simple question: if you take a substance and cut it into smaller and smaller pieces, is there a limit to how many times you can keep cutting it into smaller pieces? When this question was originally asked, back in ancient Greece around 400 BC, … Continue reading Atoms – basic ideas
What is Static Electricity?
When work is done on an object, by moving a force through a distance, the object gains energy. As a result, the object might get hotter (gain thermal energy) or accelerate (gain kinetic energy) or be lifted upwards (gain gravitational energy). There is also another possibility; the object could gain electrical energy in the form … Continue reading What is Static Electricity?
Radioactivity: Basics and Test
This post highlights the fundamental knowledge and key skills that form the basics of radioactivity. There is also a short online test for you to check your understanding. The first things you need to know are descriptions of the atom (how models have changed with time) and what causes "radioactivity". These two fundamentals are covered … Continue reading Radioactivity: Basics and Test
Atomic Number and Atomic Mass
When you learned about the Periodic Table during KS3, you were told that it lists all the elements in order of their atomic number. You should also have learned that every element has two numbers; the smaller value is the element's atomic number and the larger value is the element's atomic mass. The value for … Continue reading Atomic Number and Atomic Mass
