Fundamental Particle Definitions

1. Fundamental Particle Definitions • Matter – anything that takes up space and has mass • Atom – smallest whole particle known to man • Element – any substance that can not be broken down into other substances by chemical reactions • Compound – two or more elements that have combined in a fixed ratio • Traceelement – elements in minute quantities

2. Neutrons – a subatomic particle with a neutral charge • Protons – a subatomic particle which has a positive charge • Electrons – a subatomic particle that has a negative charge • Dalton – a unit of measurement for neutrons and protons (1.7 x 10-24) • Atomicnumber – the number of protons in the nucleus • Atomicweight – the total atomic mass of an element • Isotope – an atom that varies its form by changing the number of neutrons in the element

3. Energy – the ability to do work • Potentialenergy – stored energy due to position or location • Electronshells – the different states of potential energy for electrons in an atom • Orbital – the 3d space in which an electron is found 90% of the time, probable location. • Valenceelectrons – the outer most shell of electrons • Covalentbonds – atoms that combine by sharing valance electrons

4. Electronegativity – the attraction of an atom for the electrons of a covalent bond • Ionicbond – a type of bonding in which one atom strips away an electron from another atom • Ion – a charged atom • Hydrogenbond – occurs when a hydrogen atom covalently bonded to 1 electronegative atom is also attracted to another electronegative atom • Chemicalreaction – the making and breaking of chemical bonds • Reactants – the starting materials in a chemical reaction • Products – the result of a chemical reaction

5. Matter • Matter consists of chemical elements-anything which occupies space and has mass. • Matter is found in two ways; pure-form or compounds • The Greeks first proposed four elements that made matter; earth, air, fire, and water. • Scientists later discovered 92 naturally occurring elements • They can be man-made or naturally occurring • Two or more elements may combine to form compounds • They can be found naturally in three ways called phases; solid, liquid, and gas

6. 1. What were the first four elements? Earth Air Fire Water

7. Solid Liquid or Gas?

8. 2 3 4

9. Atoms Movie

10. Elements • There are 92 known elements (naturally occurring) • These elements are found on the periodic table of the elements • Some different elements combine together to form compounds • Table salt is a compound made up of sodium and chlorine • It is written using the abbreviation NaCl • Na = Sodium and Cl = chlorine • The 92 elements are found on the periodic table of the elements

11. Symbols for Elements • Symbols are letters that represent the elements on the periodic table 1. If only a single letter, it is Capitalized. 2. If two letters, the 1st is Capitalized and the 2nd is lower case. Example: Ca not CA

12. Periodic Table of the Elements • Check out the initials for Aluminum in this example off of the Periodic Table: 13 Al 26.98154

14. Periodic Table of the Elements • The number of protons in an atom is listed above each abbreviation. It is called the Atomic Number. 13 Al 26.98154

15. Periodic Table of the Elements • The number listed underneath the abbreviation is the Atomic Weight. 13 Al 26.98154

16. Element Acronym C Hopkins café mighty-good food never closed zundays. • C-Carbon Ca-Calcium • H-Hydrogen Fe-Iron • O-Oxygen Mg-Magnesium • P-Phosphorus F-Fluorine • K-Potassium Na-Sodium • I-Iodine Cl-Chlorine • N-Nitrogen Zn-Zinc • S-Sulfur

17. Atoms and Molecules

18. Atomic Structure • The atom is the smallest unit to have properties of an element • About one million fit onto a period at the end of a sentence • They are comprised of neutrons, protons, and electrons • Neutrons and protons are neatly packed in the nucleus • Neutrons and Protons have almost exactly the same mass • Each one has the mass of ~1.7 x 10-24 grams • Electrons are 1/2000 the size of + and N • The number of protons unique to an element is the atomic number • The atomic mass is the total of protons and neutrons in the nucleus • Proton = 1.007 Daltons Neutron = 1.009 Daltons

19. Atomic Particles

20. Structure of an Atom Electron (electron cloud) Proton Mass Number = Protons + Neutrons Atomic Number = Number of protons Neutron

21. Isotopes • When the number of protons in an atom changes it becomes a different element • Atom is electrically neutral when there are more neutrons than protons • Atoms of the same element that have a different number of neutrons are called isotopes • Ex. C12 = 6p +6n C14 = 6p + 8n

23. Ions • Electrically charged atoms are called Ions • The number of protons is not equal to the number of electrons • Ions are attracted to each other when they have opposite charges • Ex. Na+ + Cl- = NaCl = salt • Ex. Na+ + F- = Sodium Fluoride for toothpaste

24. Combinations of Atoms

25. Atoms combine by sharing their outermost electrons in their electron clouds • When two atoms are combined a molecule is formed

26. Bonds • Ionic Bond – Positive and Negative ions combine and electrons are transferred • Ex. NaCl • Covalent Bond – Electrons are shared • Ex. H2O

28. Name that term….. 1. What is the smallest particle to possess the qualities of an element? 2. Where are + and n found in an atom? 3. How do you know how many electrons are in an atom? 4. What does the atomic number represent? 5. What does the atomic mass represent?