Water & Its Solution

• Water is a compound made up of (H20) molecules.
• The oxygen and hydrogen atoms in a water compound are bonded together through covalent bonds.
• water is polar.
• The polarity of water is caused by the difference in electronegativity between oxygen (more electronegative) and hydrogen (less electronegative). This means that oxygen is slightly negative and hydrogen is slightly positive.
• intermolecuar forces (van der waal) are forces of attraction and repulsion between molecuies. These forces play an important role in the properties of

  water
• A Hydrogen Bond is a type of van der waal force that attracts the slightly positive hydrogen of one molecule with a slightly negative oxygen, nitrogen, or fluorine of another molecule.
• The properties of water: It is polar, Cohesion, Adhesion, Surface tension, Density, Universal Solvent, Naturally occurs in all 3 states, and has a High heat capacity
• Cohesion: water molecules are attracted to other water molecules.
• Admission: water molecules stick to other molecules.
• Surface tension: The top layer of water molecules are extra cohesive, allowing them to form a skin- like surface on top.
• Density: water becomes less dense when it freezes. This causes ice to float on water.
• Universal Solvent: water dissolves a lot of other substances. It's charged

  molecules attract other molecules and can dissolve them.
• Naturally occurs in all 3 states: water can be naturally found as solid (ice), liquid (water), and gas (water vapor).
• High heat capacity: It takes a lot of heat to make water hot.

  Practice
• capillary action is when water molecules tow or pull each other along a structure against the force of gravity. It is due to the properties of cohesion and Adhesion.
• There are two types of mixtures: Homogenous and heterogeneous
• Homogenous

  also called a solution

  • a mixture where you can't tell which component is which. It looks the same.
• Heterogeneous:

  -A mixture where you can tell which is which.

  It looks different.

  There are two types:

  Colloids: particles that don't settle

  Suspensions: particles settle over

  time
• Acids are substances that release H* when dissolved in water.
• Bases are substances that release hydroxide ions (OH-) when dissolved in water
• The amount of hydrogen or hydroxide ions in a solution determines the strength of an acid or base.
• PH is the measure of the concentration of H in a solution.

  • Acids have pH values<7

  •Bases have pi values >7

  • 7 remains neutral
• Buffers are mixtures that can react with acids or loases to keep the pht within a particular range.
• Battery acid has a ph of 0
• Stomach acid has a ph of 1
• Lemon juice has a ph of 2
• Vinegar has a ph of 2
• Cola has a ph of 3
• Orange juice has a ph of 3
• Tomatoes have a ph of 4
• Bananas have a ph of 5
• Normal rainwater has a ph of 5
• Urine has a ph of 6
• A healthy lake has a ph of 6
• Blood has a ph of 7
• Tears have a ph of 7
• Pure water has a ph of 7
• Seawater has a ph of 8
• Baking soda has a ph of 9
• The great salt lake has a ph of 10