Question of the day Which of the following is the most important to composition of organic life? A. Hydrogen B. Silicon C. Carbon D. Oxygen

DO NOW Sept 18 Write down three facts you recall about matter.

DO NOW ANSWERED Has mass Takes up Space Solid, Liquid, Gas

AGENDA Sept 18 BIG QUESTION: How do elements react with one another? 1. DO NOW 2. Bio Journal #2 3. Introduction to the Chemistry of Life 4. Review 2-1 Guided Reading 5. Closing Thoughts and Homework: BOHR Models for the following elements F, Al, Ti, Si, Br

Chapter 2 Introduction to Chemistry

Nature of Matter matter: anything that has mass and takes up space physical properties: characteristic of matter that can be observed and measured without permanently changing the identity of the matter examples are color, odor, shape, texture, taste, and hardness chemical properties: describes a substance’s ability to change into another new substance as a result of a chemical change determined by the sort of chemical reaction a substance can undergo

DO NOW Sept 19 Volunteers will draw BOHR Models on the boards.

Bio Journal 2 C 6 H 12 O 6 + ___ O 2  ___ CO 2 + ___ H 2 O

Balanced Equation C 6 H 12 O O 2  6 CO H 2 O

AGENDA Sept 19 How do elements form compounds? 1. DO NOW 2. Balancing Equation from Bio Journal 2 3. Chapter 1 Test 4. Elements and Isotopes 5. Closing Thoughts and Homework

Phases of Matter phases: physical property of matter that describes one of a number of different states of the same substance four phases of matter solidliquidgasplasma change from one phase to another is a physical change

2-1: The Nature of Matter atom: the basic unit of matter nucleus: center of the atom makes up 99.9% of the atom’s mass contains three subatomic particles: In the nucleus: Protons (+) and Neutrons (n) proton and neutron are nearly equal in mass Outside nucleus in energy levels: Electrons (-) have a mass 1840 times less than the proton and neutron

Question the day Sept 20 Which of the following is not a compound? A. CO B. Ti C. NaCl D. HCl

DO NOW Sept 20 Explain the difference between a physical change and a chemical change. Provide an example of a physical change. Provide an example of a chemical change.

DO NOW ANSWERED SEPT 20 A physical change does not change the identity of the matter. A chemical change is the change of a substance into a new substance having different physical properties. Physical Change: Tearing a piece of paper in half. Chemical change: Burning gasoline in an engine

AGENDA Sept 20 BIG Question: Why do elements react? 1. QOTD 2. DO NOW 3. Section 2-1: Atomic Mass and Number Elements and Isotopes 4. Closing Thoughts and Homework

HOMEWORK Textbook Page 57 UNDERSTANDING CONCEPTS THIS WILL BE HANDED IN. WRITE IN COMPLETE SENTENCES. DUE MONDAY SEPT 23

Atomic and Mass Number atomic number: number of protons in the nucleus of an atom identifies an atom mass number: the total number of protons and neutrons in the nucleus of an atom Mass of electrons are incredibly small.

Chemical Elements element: a substance which consists entirely of one type of atom 109 different elements 90 types are found in nature 19 have been artificially produced represented by a symbol, consisting of 1 or 2 letters isotope: an atom of the same element that has the same number of protons but different numbers of neutrons

Radioactive Isotopes isotopes that have nuclei that are unstable and will break down releasing matter and/or energy in the form of radiation all the isotopes of elements with atomic numbers greater than 83 are radioactive have many practical uses such as: used as tracers to study living organisms diagnose and treat diseases sterilize foods measure the ages of certain rocks

Chemical Compounds when elements combine to form substances consisting of two or more different atoms in definite proportions compounds are represented by a chemical formula

Interactions of Matter compounds are formed by the interactions of individual atoms chemical bonding: the process of combining the atoms of elements combine according to certain rules determined by the number of electrons an atom has in its outer most energy level electron energy levels can hold only certain numbers of electrons 1 st level: 2 electrons 2 nd level: 8 electrons 3 rd level: 8 electrons when the outermost energy level contains the maximum number of electrons, the level is full and the atom is stable in order to achieve stability, an atom will either gain, lose, or share electrons

Question of the Day How many bonds can an atom of oxygen form? A. 1 B. 2 C. 3 D. 4

DO NOW Sept 23 Explain how atoms react to form larger molecules.

DO NOW ANSWERED Atoms react to achieve stability. To be stable, atoms must have a completely filled outer energy level (valence shell). This is accomplished through the gaining, losing, or sharing of valence electrons.

AGENDA Sept 23 BIG QUESTION: How do elements form compounds? 1. QOD 2. DO NOW 3. Finish Section 2-1 Notes 4. Building Chemical Compounds? 5. Closing Thoughts and Review

Electron Shells Electrons surround the nucleus of an atom in electron shells or orbitals. The valence shell is the outermost shell. These electrons want to react making the atom stable.

Ionic Bond a bond that involves a transfer of electrons comes from the word ion: a charged particles ions are formed when an ionic bond occurs

Covalent Bonds a chemical bond formed by the sharing of electrons can be single, double, or triple a small number of atoms are involved in the sharing of electrons molecule: collection of two or more atoms covalently bonded

3-4: Chemical Reactions any process in which a chemical change occurs can occur slowly or quickly reactants: elements or compounds that enter into a chemical reaction products: elements or compounds produced by a chemical reactions represent chemical reactions by a chemical equation the flow of energy is important in determining whether a chemical reaction will occur reactions which release energy will occur spontaneously reactions that require energy will not occur spontaneously