1 / 12

Atoms and the Periodic Table

Atoms and the Periodic Table. Atoms are the basic building blocks of all matter. Atoms are made up of: Protons—Positively charged particles; found in the nucleus Neutrons—Particles that have no charge; found in the nucleus Electrons—Negatively charged particles; found outside the nucleus.

semah
Download Presentation

Atoms and the Periodic Table

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. Atoms and the Periodic Table

  2. Atoms are the basic building blocks of all matter. • Atoms are made up of: • Protons—Positively charged particles; found in the nucleus • Neutrons—Particles that have no charge; found in the nucleus • Electrons—Negatively charged particles; found outside the nucleus

  3. Nucleus containing two protons and two neutrons - + + - 1st energy level containing two electrons

  4. The number of protons and electrons will be the same in a neutral atom.

  5. Elements are made up of atoms. • Elements: substances that cannot be broken down into simpler chemical substances • examples: Gold, Iron, and Silver Atoms of: ELEMENT Pure Gold 18-Karat Gold 14-Karat Gold

  6. The Periodic Table is a table with all of the elements found on earth.

  7. How to Read the Periodic Table • Chemical Symbol: the letters • Atomic Number: found above the chemical symbol • Atomic Mass: found below the chemical symbol

  8. Atomic Number = # of protons (= # of electrons) • # of neutrons = atomic mass – atomic # • Isotope: Atoms of the same element that have different numbers of neutrons two isotopes of Sodium

  9. Ions: atoms that gain or lose electrons; have a positive charge (more protons-called a cation) or a negative charge (more electrons-called a anion) • Valence Electron Rule (Outermost) • 1-3 electrons- lose- positive -cation • 4- covalent bond (covalent bond-share a pair) • 5-7 electrons – gain- negative - anion • 8 –Inert because the atom is full ( Noble gases

  10. Electron Shell Diagram and Electron Dot Formula • 1st electron shell can hold 2 electrons • 2nd electron shell can hold 8 electrons • 3rd electron shell can hold 8 electrons 1st 2nd Nucleus 3rd

  11. Electron shell diagram: shows the arrangement of all the electrons surrounding the nucleus of an atom The first 2 electrons go in the 1st energy level. The other 4 electrons go in the 2nd energy level. 6 P 6 N If we have 6 protons in the nucleus, we need to have 6 electrons in the energy levels around the nucleus.

  12. Electron dot formula: shows the number of electrons in the outermost electron shell Next, you draw a dot for each electron in the outermost energy level. You can put dots on four sides of the symbol—top, bottom, left, and right. Put the dots in pairs. C First, you write the symbol for the element.

More Related