Ionic Bonds As a general rule,?metals?are on the?left?of the periodic table and?nonmetals?are on the?right-hand?side Ionic?bonding?involves the?transfer?of electrons from a?metallic?element to a?no...
Melting & Boiling Point Trends Elements in the periodic table are arranged in order of increasing atomic number and placed in vertical columns (groups) and horizontal rows (periods) The ...
NEC全美經濟學挑戰（National economic challenge）由美國經濟教育學會舉辦的經濟學學術活動。它是美國最負盛名、最具影響力的中學生經濟學學術活動。AP課程 VS NEC，2022新賽季報名中！ NEC的知識體系與多種主要...
Electronic Configurations of Atoms & Ions The?principal quantum shells?increase in energy with increasing?principal quantum number E.g.?n?= 4 is higher in energy than?n?= 2 The?su...
Orbital Shapes Orbitals Subshells contain one or more?atomic orbitals Orbitals exist at?specific?energy levels and electrons can only be found at these specific levels,?not?in between them E...
Developing Electronic Configuration Electrons move rapidly around the nucleus in energy shells If their energy is increased, then they can jump to a higher energy level The process is revers...
Factors Affecting Ionisation Energy Ionisation energy The?ionisation?Energy?(IE) of an element is the amount of energy required to remove?one mole?of electrons from?one mole?of gaseous atoms...
Interpreting Mass Spectra Isotopes are different atoms of the same element that contain the same number of protons and electrons but a different number of neutrons These are atoms of the sam...
Isotopic & Atomic Mass The relative mass of an atom uses the carbon-12 isotope as the international standard One atom of carbon-12 has an accepted mass of 1.992646538 x 10-26?kg It is not reali...
