Question

every known element has
select one:
o a. several different types of atoms
o b. a unique type of atom
o c. the same number of atoms
o d. the same type of atoms as any other element

Explanation:

An element is defined as a pure substance that consists of only one type of atom. Each element has its own unique atomic structure (e.g., number of protons in the nucleus). For example, hydrogen atoms have 1 proton, oxygen atoms have 8 protons. This uniqueness distinguishes one element's atoms from another's. Option A is incorrect because an element has only one type of atom (isotopes are still of the same element type). Option C is wrong as different elements have different amounts of atoms in samples (e.g., 1 mole of hydrogen vs 1 mole of oxygen has same number of atoms - Avogadro's number, but in general samples can vary). Option D is false as each element's atoms are distinct (e.g., carbon atoms vs gold atoms).

Answer:

B. a unique type of atom