NATS 1610 Lecture Notes - Lecture 13: Electron Shell, Relative Atomic Mass, Sodium

• School: York University
• Department: Natural Science
• Course: NATS 1610
• Professor: Barbara Czaban

Document Summary

Matter makes up everything that is of this world (living & non-living). The average value of the elements for a typical human. The cost varies due to stock market fluctuations . Chemical elements can"t be broken apart by normal means. Can"t be broken down to another substance by ordinary physical or chemical techniques. Over 90% of human body is composed of four elements. Every element has its own symbol derived from name. Each element is made entirely of one type of atom. Composed of 3 areas and 3 main types of particles: central nucleus, containing. Neutral neutrons (2: pathways around nucleus called shells, orbiting around the nucleus. Through electrical attraction to the positive protons of the nucleus. All atoms of an element have the same atomic number. Usually written as a subscript to lower left of atomic symbol. Protons & neutrons each = 1 atomic mass unit (amu) Electrons are light & have almost no mass.