Peridiocity

2. a column in the periodic table of the chemical elements
3. the number of atoms, ions, or molecules that a central atom or ion holds as its nearest neighbor in a complex or coordinate compound
4. The horizontal rows of the periodic table
7. any of the series of 15 consecutive chemical elements in the periodic table from lanthanum to lutetium.
10. any of the six chemical elements that make up Group 1 of the periodic table
13. any of a series of 15 consecutive chemical elements in the periodic table from actinium to lawrencium
14. chemical catalysts whose physical phase is different from the phase of the reactants/products that take part in the catalyzed chemical reaction.
15. any of the seven chemical elements that make up Group 18 of the periodic table.

1. a process where the reactants involved in the reaction and the catalyst are in the same phase
5. the attraction exerted by the nucleus on electrons due to the positive charge of the protons and negative charge of the electron.
6. the blocking of valence shell electron attraction by the nucleus, due to the presence of inner-shell electrons.
8. any of various metallic elements that have valence electrons in two shells instead of only one
9. a table of the chemical elements arranged in order of atomic number in rows and columns.
11. any of the six nonmetallic elements that constitute Group 17 of the periodic table
12. an ion or molecule attached to a metal atom by coordinate bonding