A look at water and its contaminants
Download
1 / 27

A Look at Water and Its Contaminants - PowerPoint PPT Presentation


  • 106 Views
  • Uploaded on

A Look at Water and Its Contaminants. Water Part B. Physical Properties of Water. Matter anything that occupies space and has mass. Physical Properties of Water. Physical Properties : can be observed or measured without changing the identity of a sample of matter Examples:

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'A Look at Water and Its Contaminants' - lang


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
A look at water and its contaminants

A Look at Water and Its Contaminants

Water Part B


Physical properties of water
Physical Properties of Water

  • Matter

    • anything that occupies space and has mass


Physical properties of water1
Physical Properties of Water

  • Physical Properties: can be observed or measured without changing the identity of a sample of matter

  • Examples:

    • Boiling point, melting point, density, color


Physical properties of water2
Physical Properties of Water

  • Density: mass  volume

  • the density of liquid water is 1.00 g/mL


Physical properties of water3
Physical Properties of Water

  • Physical state affects density:

    • gases are much less dense than liquids

    • solid form of a substance is usually denser than its liquid form

    • EXCEPT WATER: As water freezes it occupies a larger volume (d = 0.92 g/mL)

  • the density of liquid water is 1.00 g/mL


Physical properties of water4
Physical Properties of Water

  • clear, odorless, colorless, and tasteless

  • easily changes to each of the three phases of matter

  • “universal solvent”- so many substances easily dissolve in water to make aqueous solutions.


Physical properties of water5
Physical Properties of Water

  • high boiling point 100 C

  • high surface tension


Mixtures and solutions
Mixtures and Solutions

  • Mixture: two or more substances are mixed together and they keep their individual properties

    • Heterogeneous mixture: a mixture that is not uniform throughout

      • Example: Chocolate chip cookie

    • Homogeneous mixture (Solution): a mixture that is uniform throughout

      • Example: Peanut Butter Cookie


Mixtures and solutions1
Mixtures and Solutions

  • Mixtures are classified by size of the particles in the mixture.


Mixtures and solutions2
Mixtures and Solutions

Solution- smallest particle size,

  • salt water

  • Solute- substance that is dissolved

  • Solvent- substance that does the dissolving

  • Kool-Aid


Mixtures and solutions3
Mixtures and Solutions

  • Colloid-medium particle size,

    • Fog

  • Shows the Tyndall Effect light is scattered in many directions and can easily be seen.

  • like seeing dust particles in the light beam of a light


  • Mixtures and solutions4
    Mixtures and Solutions

    • Suspension-largest particle size,

      • medicine that says “shake before using”


    Particulate view of water
    Particulate View of Water

    • Atoms: All matter is composed of atoms; smallest particles possessing the properties of an element

    • Element: matter that is made up of only one kind of atom

    • oxygen is an element because it is composed of only oxygen atoms

    • 90 elements are found in nature!


    Particulate view of water1
    Particulate View of Water

    • Compound: substances composed of two or more elements linked together chemically in fixed proportions

    • water H2O

    • table salt NaCl

    • ammonia NH3

    • baking soda NaHCO3

    • chalk CaCO3


    Symbols formulas equations
    Symbols, Formulas & Equations

    • Chemical Symbols: the international language of chemists and scientists across the planet

    • each element is assigned a symbol

    • the first letter is capitalized; all other letters are lowercase

    • Al, Cl, Ag, Mg


    Symbols formulas equations1
    Symbols, Formulas & Equations

    Subscripts: a number written below which indicates the number of atoms of each element that are present in a substance 

    H2O 2 Atoms of hydrogen

    1 Atom of oxygen

    C3H8 3 Atoms of carbon

    8 Atoms of hydrogen


    Symbols formulas equations2
    Symbols, Formulas & Equations

    • Chemical reactions: creating new substances

    • the new substances have completely different properties than the original substances.

      2H2 + O2 2H2O

      Hydrogen + Oxygen  Water

      Reactants  Products


    Symbols formulas equations3
    Symbols, Formulas & Equations

    • Diatomic molecules: elements that exist as two bonded atoms of the same element

    • H2, N2, O2, F2, Cl2, Br2 & I2

    • All other elements are written at single atoms (Ca, Fe, Na & Mg)


    The electrical nature of matter
    The Electrical Nature of Matter

    • Remember: LIKE CHARGES REPEL AND UNLIKE CHARGES ATTRACT!

    • Atoms have:

      • Protons- positive

      • Electrons- negative

      • Neutrons-neutral (no charge)


    The electrical nature of matter1
    The Electrical Nature of Matter

    • Let’s try

      • An atom has:

        • 15 protons + 15 electrons =

        • 20 protons + 21 electrons =

        • 19 protons + 18 electrons =

        • 10 protons + 12 electrons=


    The electrical nature of matter2
    The Electrical Nature of Matter

    • Opposites attract-

      • this is the glue to hold atoms together

      • These are chemical bonds.


    Ions and ionic compounds
    Ions and Ionic Compounds

    • Ions:

      • charged atoms;

      • atoms that have gained or lost electrons to form negative or positive ions

    • Ionic Compounds: compounds composed of positive and negative ions


    Ions and ionic compounds1
    Ions and Ionic Compounds

    • Cation: a positively charged ion (Na+)

    • Anion: a negatively charged ion (Cl-)

    • Polyatomic ion: (many-atoms) an ions made of two or more bonded atoms (NH4+ or NO3-)


    Ions and ionic compounds2
    Ions and Ionic Compounds

    • Step 1: Write the symbols for the ions side by side, with the positive ion (or most metallic element) first

    • Step 2: Cross over the charge values to give subscripts

    • Step 3: Check the subscripts by making sure the total charge of ions in the compound is zero, simplify

    • Step 4: Write the formula


    Ions and ionic compounds3
    Ions and Ionic Compounds

    • Let’s try: Need to use ion chart

    • zinc oxide

    • aluminum sulfide

    • calcium carbonate


    Ions and ionic compounds4
    Ions and Ionic Compounds

    • Naming Compounds

      • Nomenclature: the method of naming chemical compounds

        1. write the name of the element having a positive charge

        2. add the name of the negative element

        3. the negative element must be modified to end in –ide


    Ions and ionic compounds5
    Ions and Ionic Compounds

    • Let’s try: Use the chart of ions

    • NaI2

    • K2O

    • BaSO4