Matter, Atoms, and Molecules Notes PDF

MATTER SLIDESMANIA.COM  6th Grade MATTER: PARTICLE, PHASES, PROPERTIES, CHANGES, CLASSIFICATION SLIDESMANIA.COM  MATTER...

MATTER SLIDESMANIA.COM  6th Grade MATTER: PARTICLE, PHASES, PROPERTIES, CHANGES, CLASSIFICATION SLIDESMANIA.COM  MATTER 01 02 -it refers to all substances that - Anything that occupies make up the universe space and has mass 03 -all matter is made up of minute and indestructible particles called atoms (Democritus) 04 -matter may be classified as pure substance and SLIDESMANIA.COM mixtures Vacuum- any volume of space that does not have any matter in it.  ATOM -Greek philosopher Democritus rationalized that matter is made up of minute and indestructible particles called atomos. Small indestructible particles basic building blocks of matter consist of even tinier particles. Neutrons, Protons, and Electrons are the basic particles making up the atom. SLIDESMANIA.COM  Particulate Terminologies Atoms are particles that define a chemical element. As elements are the most basic form of matter, then atoms are the basic units of matter. SLIDESMANIA.COM  Early Discoveries Atomism Ancient Greeks put forward the idea of Atomism, proposed by Democritus. Everything is composed of atoms, which are physically indivisible and indestructible. ”Atom” comes from the Greek word “atomos”, meaning “indivisible”. Democritus, “the laughing philosopher”, is a central figure in the development of the Atomic Theory of the universe. SLIDESMANIA.COM  Early Discoveries Atomic Theory John Dalton, an English school teacher, used the Law of Conservation of Mass and Law of Constant Composition as the basis of the Atomic Theory. His theory involved the following assumptions: A. Each element is composed of extremely small particles called atoms. SLIDESMANIA.COM B. All atoms of a given element are identical, but the atoms of one element are different from the atoms of all other elements.  Early Discoveries Atomic Theory C. Atoms of one element cannot be changed into atoms of a different element by chemical reactions; atoms are neither created nor destroyed in chemical reactions. D. Compounds are formed when atoms of more than one element combine; a given compound always has the same relative number and kind of atoms. SLIDESMANIA.COM  Parts of ATOM Atoms consist of three basic particles: protons, electrons, and neutrons. ❖ The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged). Nuclear Model- The model of an atom that has the protons and neutrons in a central nucleus with the electrons in orbit about the nucleus. Proposed by Ernest Rutherford SLIDESMANIA.COM NOTE: Atoms have different properties based on the arrangement and number of their basic particles.  Subatomic Particles The nucleus (N+) is the small, dense region consisting of protons and neutrons at the center of an atom. SLIDESMANIA.COM Almost all the mass of the atom is concentrated in the nucleus.  Particulate Terminologies Subatomic Particles Protons (p+) are positively charged particles found in the nucleus of the atom. The proton has a charge of +1: SLIDESMANIA.COM Protons are composed of two up and one down quarks.  Particulate Terminologies Subatomic Particles Neutrons (n0) are negatively charged particles in the nucleus of the atom. The neutron has a charge of 0: SLIDESMANIA.COM Neutrons are composed of one up and two down quarks.  Protons and neutrons are referred to as nucleons. SLIDESMANIA.COM  Particulate Terminologies Electrons are free-moving particles around the nucleus. These particles are important in chemical processes, as electrons interact to form or break bonds. SLIDESMANIA.COM Interactions of electrons cause chemical bonding.  How to determine the number of protons, electrons and number of neutrons? in an atom, use its atomic number and mass number: 1. number of protons = atomic number. 2. number of electrons = atomic number. 3. number of neutrons = mass number - atomic number. 4. mass number = protons + neutrons How to Determine the number of electrons from proton number If it is a neutral atom, the number of electrons is equal to the proton number SLIDESMANIA.COM If the ion is positively charged, the number of electrons is found by subtracting the charge number from the proton number. If the ion is negatively charged, the number of electrons is found by adding the charge number to the proton number.  Atomic Number 𝐴 𝑋 (proton and electron number) Symbol of the Element Mass Number Z How to identify the charge of an atom? The charge of an element is the # of protons - # of electrons. For example, a chlorine atom that gains an electron will have a charge of -1 because 17 - 18 = -1 (17 protons, 18 electrons) Remember: if there are more protons than electrons, then the atom is positively charged. If there are more electrons than protons, the atom is negatively charged. - The atomic number is equal to the number of PROTONS  MOLECULES a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction. SLIDESMANIA.COM When atoms combine, they form molecules. A molecule is a group of two or more atoms that form the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance. Molecules can be simple, complex, or even repeating units.