The diameter of a nucleus varies depending on the type of atom and its atomic number. On average, the diameter of a nucleus is typically in the range of 1 to 10 femtometers (1 femtometer = 10^-15 meters).
The size of a nucleus is determined by the number of protons and neutrons it contains, which in turn determines its mass. As the number of protons and neutrons increases, the nucleus becomes larger. However, the density of the nucleus remains incredibly high, as most of the mass is concentrated in a very small volume.
For example, the diameter of a hydrogen nucleus (consisting of a single proton) is estimated to be around 1.75 femtometers, while larger nuclei like uranium-238 can have diameters around 14 femtometers. It's important to note that these values are approximate and can vary slightly based on experimental measurements and theoretical models.