Physical sci Crossword

the theory that all matter is made up of tiny indivisible particles
born in Cumberland, reworked Democritus' theory, as follows: All matter is formed of atoms. That atoms are indivisible and invisible particles. That atoms of the same element are of the same type and mass.
scientists of modern physics, best known for his substantial contributions to quantum theory and his Nobel Prize-winning research on the structure of atoms. Born in Copenhagen in 1885 to well-educated parents, Bohr became interested in physics at a young age.
published his periodic table of elements in 1869. His table arranged the known elements according to their chemical properties and in order of their relative atomic mass. This created several gaps in the periodic table and allowed him to predict eight other undiscovered elements correctly.
the basic unit of a chemical element.
a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign.
a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
was a Polish scientist who won a Nobel prize in both Chemistry and Physics. She made ground-breaking work in the field of Radioactivity, enabling radioactive isotypes to be isolated for the first time.
a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
the central and most important part of an object, movement, or group, forming the basis for its activity and growth.
the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.
is a notation of one or two letters representing a chemical elemen
is a notation of one or two letters representing a chemical elemen
any of the gaseous elements helium, neon, argon, krypton, xenon, and radon, occupying Group 0 (18) of the periodic table
is a term used to describe the size of the atom, but there is no standard definition for this value.