Unit 2 Organic Molecules

The Universal Solvent- Water Day 1 The Universal Solvent- Water

Remember color code Blue- to help you remember Red- Important point to know Green- definition that’s needed

Background Information Atom- basic unit of matter Proton and neutron- subatomic particles in the nucleus Electron- subatomic particle in charge of bonding on the outside of the nucleus Covalent Bond- bond in which electrons are shared Ionic bond- bond in which electrons are donated or received Hydrogen bond- bond caused by differences in charges on a polar covalent molecule

Why is water SO important? Water is polar which makes it the universal solvent Hydrophilic- polar substances that are easily dissolved In water (i.e. sugar) Hydrophobic- nonpolar substances that are not easily dissolved in water (i.e. oil) Has a neutral pH (acidity vs. basicity) Water forms H+ and OH- ions Can act as a buffer- substances that resist changes in pH

Why is water SO important? 3. Water has a high specific heat Specific heat is how much heat is required to change the temp of a substance by 1 degree Able to help normalize temperature changes 4. Water floats when it freezes Why would this be important?

Why is water SO important? 5. Cohesion and Adhesion- Cohesion- Water is attracted to water molecules Creates surface tension Adhesion-Water is attracted to other substances Why are these concepts important? 6. Allows for molecules to synthesized or hydrolyzed Synthesis- put together Hydrolysis- break apart

pH scale Compares how acidic substances are 0- 6 is acidic 7 is neutral 8-14 is basic

Buffers Weak acids or bases in a cell that serve as protection against changes in pH Our blood is a buffer solution maintaining a neutral pH of about 7.35- very close to waters pH

Most Important Elements to Living Things: C, H, N, O, P, S Carbon Hydrogen Nitrogen Oxygen Phosphorus Sulfur