Atomic structure from a physical perspective – basic principles
How it works
Atoms consist of a positively charged atomic nucleus (protons and neutrons) and a negatively charged electron shell. The number of protons (atomic number) determines the element. Neutrons influence the mass number and the isotope type. Electrons are arranged in certain energy levels. The electric charge of an atom is balanced in the neutral state. The mass of the atom is determined mainly by the nucleus, while the size of the atom is determined above all by the electron shell. Models such as the shell model help describe the distribution of electrons.
The structure of an atom is determined by the number and arrangement of protons, neutrons and electrons. The number of protons defines the chemical element, the number of neutrons influences the isotope type, and the number of electrons determines the charge.
An example
How many protons are in the nucleus of an oxygen atom (atomic number 8)?
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.