1 / 24

Chapter 2 Chemistry

Chapter 2 Chemistry. Chemistry. Matter  anything that has mass & takes up space Mass  amount of matter an object has Elements  pure substances that cannot be broken down into simpler kinds of matter Important elements : C, O, H, N. Chemistry.

christiang
Download Presentation

Chapter 2 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. Chapter 2 Chemistry

  2. Chemistry • Matter  anything that has mass & takes up space • Mass amount of matter an object has • Elements pure substances that cannot be broken down into simpler kinds of matter • Important elements : C, O, H, N

  3. Chemistry • Atom  simplest particle of an element  the properties of an atom determine the properties of that matter • Nucleus  core of an atom ; protons & neutrons • Protons  + charge , mass 1 amu • Electrons  - charge, no mass • Neutrons  no charge, mass 1 amu

  4. Electrons  outside the nucleus on shells 2 on the first & 8 on the rest

  5. Periodic Table • Arranged in increasing atomic # • Atomic # = number of protons • # of Protons = number of electrons • Atomic mass = # of protons + # of neutrons • Each column has the same number of outside ( valence electrons)

  6. Chemistry • Compound  pure substance of 2 or more elements combined H2O, CH4, (NH4)2SO4

  7. Bonds • Bonds  attachments of atoms in a compound • Covalent  electrons shared • Ionic  1 atom gains electrons & 1 atom loses

  8. Chemistry • Molecule  simplest part of a substance that has all the properties of that substance and can exist by itself  can be two atoms of the same element or more than one type of element • Ex: O2, N2, C6H12O6

  9. Chemistry • Reaction  two substances interact & change identity Reactants ------ Products H2 + O2→ 2H2O ↔ Means that the reaction can go both ways

  10. Chemistry • Exothermic reactions that release heat/ energy • Endothermic  reactions that absorb heat/energy • Activation energy  energy needed to start a reaction

  11. Chemistry • Catalyst  speed up reactions by lowering activation energy • Enzymes  are biological catalysts • Substrate substance that binds to enzymes

  12. Enzymes Functions • Are substrate specific • Lock & key fit • Speed up reactions by lowering activation energy

  13. Chemistry • Solutions  are mixture where one substance is dissolved in another • Solute  substance that gets dissolved Ex: Kool Aid Powder • Solvent  does the dissolving Ex: Water – water is the universal solvent

  14. Chemistry • Concentration  amount of solute per amount of solution  tells us how spread out the particles are • Saturated  no more solute can be added  it has the maximum amount of solute • Aqueous  something is dissolved in water (aq)

  15. Chemistry • Dissociation of water H2O ↔ H+ + OH- hydrogen ion + hydroxide ion • Ions  are any particle that has a charge

  16. Chemistry • ACIDS & BASES • Acids  form hydrogen ions in solution (H+ )  have a sour taste Ex: HCl  H+ + Cl- • Bases  form hydroxide ions in solution (OH-)  have a bitter taste Ex: NaOH  Na+ + OH –

  17. Chemistry • pH Scale  measures the concentration of hydrogen ions in solution  Range is 0-14  0 – 7 is an acid  7- 14 is basic (alkaline) → 7 is neutral (water) • Buffer  substances that neutralize a small amount of acid or base.  maintain the pH within our bodies.

More Related