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Basic Chemistry. What is matter?. Matter is anything that takes up space and has mass. Solid Liquid Gas. What is Energy?. Energy is the ability to do work or to put matter into motion. Kinetic energy- Movement Potential energy- Stored energy
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What is matter? • Matter is anything that takes up space and has mass. • Solid • Liquid • Gas
What is Energy? • Energy is the ability to do work or to put matter into motion. • Kinetic energy- Movement • Potential energy- Stored energy All living things are built of matter. Therefore in order to grow and function, they need a continuous supply of energy.
In your groups try and list as many forms of energy as you can? Also, give a list of any sources of energy.
Forms of Energy • Chemical energy • Energy stored in bonds of chemical substances • All body activities are done by chemical energy
Forms of Energy • Electrical energy results from the movement of charged particles. • In the body, an electrical current is generated when charged particles move across cell membrane.
Forms of Energy • Mechanical energy • Directly involved with moving matter • Muscles in your body relax and contract to cause movement.
Forms of Energy • Radiant energy travels in waves. • X-rays, infrared, visible light, radio, ultraviolet • Light energy stimulates retinas of your eyes to produce vision. • Ultraviolet waves stimulate our bodies to produce vitamin D.
In your groups, discuss any circumstances where one energy form is converted into another.
Energy Form Conversions • Electricity from socket is converted to light by lamp. • Chemical energy of ATP is converted to electricity of nervous system or mechanical energy of muscles.
Can energy be destroyed or created? • No, energy cannot be created or destroyed.
Energy Form Conversions • EFC are quite inefficient because some energy is always lost to the environment as heat. • Not lost but unusable
The Atom • The nucleus of an atom is made of protons and neutrons. • Proton is a tiny particle that has mass and a positive electrical charge • Neutron is a particle with approximately the same mass as a proton but with no charge. • Electron (e-) has little mass but has a negative electric charge.
Atomic Symbol • On the periodic table, all elements are identified by one, two, or three letter abbreviations.
What does the atomic number represent? • The atomic number represents the number of protons found in that element’s nucleus. • Hydrogen atomic number = 1. • It has one proton in its nucleus
What is the mass number? • The total number of protons and neutrons is equal to the mass number. • Electrons are too small to contribute to mass number.
What are isotopes? • Isotopes are atoms of the same element have different mass numbers. • Different number of neutrons. • Cl-35 and Cl-37
What are the four most common elements of the human body? • Oxygen 65% • Carbon 18.5% • Hydrogen 9.5% • Nitrogen 3.2% • Other 3.9%
Ions • Atoms that gain or lose electrons have a net chemical charge and is called an ion. • Na+ • Mg+2 • Si +4 • O-2
What is a molecule? • Molecules are formed when two or more atoms combine chemically. H (atom) + H (atom) → H2 (molecule)
What is a Compound? • A Compound forms when two or more different atoms bind to form a molecule. 4H + C = CH4 (methane) Compounds always have properties quite different from the atoms making them.
Filling energy levels • Electrons are distributed over one or more energy levels in a predictable pattern. • 1st inner most energy levels holds 2 electrons. • Each energy level afterwards holds 8 electrons.
What are valence electrons? • Valence electrons are found on the outermost energy levels and determine the chemical behavior of the different elements.
What is an ionic bond? • Ionic bonds form when electrons are completely transferred from one atom to another. Example: • Na(+) + Cl(-) → NaCl
What is a covalent bond? • Covalent bonds occur when molecules share electrons. For example: Hydrogen atom + Hydrogen atom → Molecule of Hydrogen gas
What is a hydrogen bond? • Hydrogen bonds are weak bonds that form between polar hydrogen compounds. • Water’s high surface tension • Allows water strider to walk on water • Help maintain structure of proteins
What is a chemical reaction? • Chemical reactions involve the making or breaking of bonds between atoms.
What is a Synthesis Reaction? • Synthesis Reaction occur when two or more atoms or molecules combine to form a larger, more complex molecule. • Energy-Absorbing Reactions • Energy absorbed in bonds • Important for growth or repair of worn-out or damaged tissue A + B → AB
What is a Decomposition Reaction? • Decomposition Reactions occur when a molecule is broken down into smaller molecules. • Chemical energy is released as bonds break. • Digestion of food into their building blocks AB → A + B
What is an Exchange Reaction? • Exchange reactions occur when there is a switch made between molecule parts and different molecules are made. • Involves both synthesis and decomposition reactions • Occurs between ATP and glucose to produce ADP and glucose-phosphate effectively trapping the glucose fuel molecule into the cell. AB + C → AC + B or AB + CD → AD + CB