The substances which cannot be separated are called elements.
<h2>Explanation:</h2>
An element is a type of particle having a similar number of protons in their nuclear cores. For instance, the nuclear number of oxygen is 8, so the component oxygen comprises all iotas which have 8 protons.
One hundred eighteen elements have been recognized: the initial 94 happen normally on Earth, and the rest 24 are manufactured ones. There are 80 components that have at any rate one stable isotope and 38 that have solely radionuclide, which rot after some time into different components.
