Across
- 1. :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.
- 3. table : The periodic table is a tabular array of the chemical elements organized by atomic number, from the element with the lowest atomic number, hydrogen, to the element with the highest atomic number, oganesson.
- 5. mass : mass number, in nuclear physics, the sum of the numbers of protons and neutrons present in the nucleus of an atom.
- 6. : 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.
- 8. number : 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.
Down
- 2. : a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
- 4. : A substance that cannot be broken down into simpler substances by chemical means.
- 5. : the basic unit of a chemical element.
- 6. :A period is the name given to a horizontal row of the periodic table .
- 7. : The vertical column of the periodic table that signifies the number of valence electrons in an element.