Presentation is loading. Please wait.

Presentation is loading. Please wait.

The Nature of Matter Section 2-1 Biology 102. Chemistry Study of chemistry begins with the atom Atom – basic unit of matter Means indivisible.

Similar presentations


Presentation on theme: "The Nature of Matter Section 2-1 Biology 102. Chemistry Study of chemistry begins with the atom Atom – basic unit of matter Means indivisible."— Presentation transcript:

1 The Nature of Matter Section 2-1 Biology 102

2 Chemistry Study of chemistry begins with the atom Atom – basic unit of matter Means indivisible

3 Atom Contains subatomic particles Proton Positive charge Neutron No charge Highest mass Electron Negative charge Constantly in motion and high energy motion keeps electrons outside nucleus

4 Atom Nucleus – Center of atom that contains protons and neutrons All atoms are neutral P = E Atomic # - number of protons Atomic mass – protons + neutrons

5 Elements and Isotopes Element – pure substance that consists entirely of one type of atom Over 100 known 12 common in living organisms Ex: C, H, N

6 Isotopes Isotope – atoms of the same element with differing number of neutrons Identified by their mass numbers (average) All isotopes have the same chemical numbers Ex: hydrogen, deuterium, tritium

7 Radioactive Isotopes Unstable nuclei and nuclei break down over time Radiation is dangerous, but can be advantageous

8 Chemical Compouds Compounds – two or more elements combined together Ex: H 2 0, NaCl Physical and chemical properties of the compound differ from the original elements Ex: NaCl

9 Chemical Bonds Atoms do not have the same ability to attract electrons Due to this, usually one atom in a bond will pull the electrons closer to it than the other atom. Creates partial negative and positive charges Creates van der Waals forces Slight attraction that develops between oppositely charged regions of nearby molecules. Ex: Gecko


Download ppt "The Nature of Matter Section 2-1 Biology 102. Chemistry Study of chemistry begins with the atom Atom – basic unit of matter Means indivisible."

Similar presentations


Ads by Google