CLASS 8 · LEARNING KNOWLEDGE
Atomic nucleus and electron shell – basic principles
How it works
Atoms consist of an atomic nucleus (protons and neutrons) and an electron shell (electrons). The number of protons determines the element. Electrons are negatively charged, protons positively, neutrons neutral. The mass of an atom lies almost entirely in the nucleus. Electrons move in certain energy levels around the nucleus. The number of electrons in a neutral atom corresponds to the number of protons.
Note
The atomic nucleus contains protons and neutrons, the electron shell contains electrons; the number of protons determines the element and the number of electrons in a neutral atom.
The atomic nucleus contains protons and neutrons, the electron shell contains electrons; the number of protons determines the element and the number of electrons in a neutral atom.
An example
How many electrons does a neutral oxygen atom have?
Oxygen has 8 protons, therefore a neutral oxygen atom also has 8 electrons.
Try it yourself now
50 Exercises · three difficulty levels · selection and number input
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: KMK Educational Standards Mathematics ESA/MSA. The topic assignment may vary by federal state.