because chemical reactions rely on the donation, acceptance and/or sharing of electrons - if the number of electrons remains the same, the chemical behavior tends to remain the same (and isotopes of the same element will all have the same number of electrons and valence shell occupations).
Isotopes of the same element have the same number of protons. They will also have the same number of electrons in a neutral state. Where they differ is in the number of neutrons in the nucleus. The chemical properties of an element are almost entirely determined by its electron structure, since chemical bonds can be understood as the transfer or sharing of electrons. This means isotopes of the same element will behave in the same way chemically. They will form the same chemical compounds and be largely indistinguishable from their isotopic brethren.
Chemically isotopes (excepting H,D,T) are identical.
Both are chemical elements, solid, metals, radioactive, having fissile isotopes, chemically reactive, toxic etc.
Isotopes are atoms of the same elements with different number of neutrons.
Isotopes are forms of the same element that differ in Neutrons.
Elements that are chemically similar to each other belong to the same group in the periodic table. They have similar chemical properties due to having the same number of valence electrons, which influences how they react with other elements. Examples include the alkali metals (Group 1) and the halogens (Group 17).
Isotopes of elements are atoms with the same number of protons but different numbers of neutrons. This causes isotopes of the same element to have different atomic masses. Isotopes can be stable or unstable, with unstable isotopes undergoing radioactive decay.
Selenium is chemically similar to sulfur as it belongs to the same group in the periodic table (group 16). Both elements have similar chemical properties and can exhibit analogous oxidation states in chemical reactions.
For the same element, isotopes have equal numbers of protons but different numbers of neutrons. Isotopes of a given element have similar chemical properties due to having the same number of electrons, which determines an element's chemical behavior.
A mixture is an association of elements and compounds but without chemical bonding. Compugs contain chemical elements chemically bonded. An element contain the same type of atoms, including isotopes.
All isotopes of a substance are chemically the same. It is their physical properties which are different.
Isotopes are atoms of the same element with different numbers of neutrons. Some elements have more than one isotope and some don't. The isotopes of an element are chemically identical, they just differ in mass. There is nothing special about any particular isotope, elements with them are just as 'regular' as the few which don't.