1 / 25

CHEMISTRY

CHEMISTRY. Atoms: The Building Blocks of Matter Southern Boone County HS William Palmer. CHEMISTRY - Atoms the Building Blocks of Matter. Democritus- Greek 400 B.C.E. Defined ATOM as indivisible. CHEMISTRY - Atoms the Building Blocks of Matter. Aristotle- Greek Followed Democritus

slade-mclean
Download Presentation

CHEMISTRY

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CHEMISTRY Atoms: The Building Blocks of Matter Southern Boone County HS William Palmer

  2. CHEMISTRY- Atoms the Building Blocks of Matter • Democritus- • Greek • 400 B.C.E. • Defined ATOM as indivisible

  3. CHEMISTRY- Atoms the Building Blocks of Matter • Aristotle- • Greek • Followed Democritus • Did not believe in atoms • Set chemistry back for 2,000 years

  4. CHEMISTRY- Atoms the Building Blocks of Matter • 1700s ideal that an element cannot be broken down by ordinary chemical means. • Questioned if elements always combine in the same ratios form a compound.

  5. CHEMISTRY- Atoms the Building Blocks of Matter • Chemical Reaction: Transformation of a substance or substances into one or more new substances.

  6. CHEMISTRY- Atoms the Building Blocks of Matter • Law of Conservation of Mass: Mass is neither created nor destroyed during ordinary chemical reactions.

  7. CHEMISTRY- Atoms the Building Blocks of Matter • Law of Definite Proportions: A chemical compound contains the same elements in the same proportions regardless of the size or source of the compound.

  8. CHEMISTRY- Atoms the Building Blocks of Matter • Law of Multiple Proportions: If two or more compounds are composed of the same elements, the ratios of the masses of the elements are small whole numbers.

  9. CHEMISTRY- Atoms the Building Blocks of Matter • Dalton’s Atomic Theory: • 1808 Dalton • English • Theory used to explain previous laws

  10. CHEMISTRY- Atoms the Building Blocks of Matter • Dalton’s Atomic Theory: • 1) Matter is composed of small particles called atoms • 2) All atoms of the same element are identical; different atoms are different • 3) Atoms cannot be subdivided, created, or destroyed • 4) atoms combine in simple whole number ratios to form chemical compounds • 5) In chemical reactions, atoms are combined, separated, or rearranged

  11. CHEMISTRY- Atoms the Building Blocks of Matter • Dalton’s Atomic Theory: • Some slight modifications based on nuclear chemistry and our understanding of atomic structure. THE BIG PICTURE All matter is composed of atoms Atoms of one element differ in properties from another atom

  12. CHEMISTRY- Atoms the Building Blocks of Matter • STRUCTURE OF THE ATOM • ATOM = The smallest part if an element that retains the chemical properties of the element. • Two Regions • Nucleus-small, center of atom • Protons, positive charge • Neutrons, neutral charge • Electron Cloud, very large • Electrons, Negative charge

  13. SUBATOMIC PARTICLES CHEMISTRY- Atoms the Building Blocks of Matter

  14. CHEMISTRY- Atoms the Building Blocks of Matter • STRUCTURE OF THE ATOM

  15. CHEMISTRY- Atoms the Building Blocks of Matter • COUNTING ATOMS • Atomic Number (Z) • Number of protons in each atom of the element • Look at Periodic Table for Z

  16. CHEMISTRY- Atoms the Building Blocks of Matter • COUNTING ATOMS • Isotopes • Some atoms have different numbers of neutrons • Different numbers of neutrons affect weight of an atom • So, Isotopes of the same element have different masses (due to the number of neutrons)

  17. CHEMISTRY- Atoms the Building Blocks of Matter • COUNTING ATOMS • Hydrogen-three isotopes • PROTIUM = 1 proton • DUTERIUM = 1 proton, 1 neutron • TRITIUM = 1 proton, 2 neutrons • All occur in nature, deuterium and tritium very rare • Tritium is radioactive

  18. CHEMISTRY- Atoms the Building Blocks of Matter • MASS NUMBER • Number of protons and neutrons in the nucleus of an isotope Mass number – atomic number = number of neutrons • Nuclide is a general term for a specific isotope of an elemet

  19. CHEMISTRY- Atoms the Building Blocks of Matter

  20. CHEMISTRY- Atoms the Building Blocks of Matter RELATIVE ATOMIC MASS Based on Carbon -12 atom 1 amu is 1/12 mass of a carbon-12 atom

  21. CHEMISTRY- Atoms the Building Blocks of Matter AVERAGE ATOMIC MASS Note that atomic weights on the Periodic Table are not simple whole numbers. This is due to the relative abundance of each isotope of the element We will round the atomic mass to two decimal places for use in our calculations.

  22. CHEMISTRY- Atoms the Building Blocks of Matter THE MOLE A mole (mol) is the amount of a substance that contains as many particles as the are in 12 g of carbon-12

  23. CHEMISTRY- Atoms the Building Blocks of Matter AVAGADRO’S NUMBER The number of particles in exactly one mole of a pure substance 6.022 1415 x 10 23 or 6.022 x 10 23 IF EVERY PERSON ON EARTH WORKED TO COUNT THE ATOMS IN ONE MOLE AT THE RATE OF ONE ATOM/SEC, IT WOULD TAKE 3,000,000 YEARS TO COUNT ALL THE ATOMS

  24. CHEMISTRY- Atoms the Building Blocks of Matter MOLAR MASS An alternate definition of mole is the amount of a substance that contains an Avogadro's number of particles. 1 mol He = 4 g 1 mol Cu = 64 g The mass of one mole of a pure substance is called the molar mass

  25. CHEMISTRY- Atoms the Building Blocks of Matter WRAP-UPS 1. Qs 1-2, page 71 2. Qs 1-4, page 76 3. Qs 1-6, page 87 4. Copy chart on top of 84 onto a card stock keep for Celebration of Knowledge 5. Qs 7-16, page 89 6. Problems 17-23 page 89-90

More Related