Unit 1 Lesson 1The Chemistry of Biology

Proton, Electron, and Neutron

Proton – _______________________that make up part of the _____________ of an atomNeutron – ______________________that make up part of the nucleus of an atomElectron – _______________________that encircle the nucleus. ___________________________________The number of ____________________________________________________________________________________________ in a neutral atom.

Periodic Table of Elements

Atomic Weight

1 proton = ___ measure of weight1 neutron = ___ measure of weight1 electron = ___ measure of weightSo…______________________________________________________

To find the number of neutrons:______________________________________________________

Drawing Diagrams

Bohr DiagramsHydrogen Carbon Oxygen

Electron Dot Diagrams

Bonding

Atoms try to fill their ___________________________________. They do this by either ___________________________________ electrons. Atoms also do this by _______________ with other atoms. Atoms that want to give away electrons will bond with atoms that want to gain electrons.

Example: NaClNa has ____ electrons, ___in its valence shell and wants to give ____ awayCl has ____ electrons, ____ in its valence shell and wants to gain ____ electron

Types of Bonds1. Ionic Bonds - actually _______________________the electron to its partner.

2. Covalent Bonds – the two atoms ___________________ the electrons. By

sharing electrons both atoms will have full valence shells

3. Polar Covalent Bonds – atoms share the electrons ____________________. One

atom is much bigger that the other and holds the electron closer giving a

_______________________________________________________________________________

_____

4. Hydrogen Bonds – polar covalent bonds create molecules that are ___________

_________________________________________ The slight positive H of one molecule

is attracted to the slightly negative O of another molecule. This creates a weak

bond we call Hydrogen bonds

Examples of Bonds

Ionic Bonds

Covalent Bonds

Polar Covalent Bonds

Hydrogen Bonds

Energy

There are two types of energy1. Kinetic Energy –

_________________________________2. Potential Energy –

_______________________________

Energy is stored in ______________ (potential energy) when bonds are ________________, energy is _____________ (kinetic energy) when bonds are ______________, energy is ___________________.

Chemical Reactions

Chemical reaction where atoms are joined together or split apart are represented by symbols in equation form.Example:If carbon is burned in the presence of oxygen, it will combine with oxygen to form carbon dioxide. C + O2 CO2

What this means is that 1 atom of carbon + 1 molecule of oxygen react or yield to form 1 molecule of CO2.

Parts of a Chemical Equation

2H2 + O2 2H2OAll the atoms on the left side of the arrow are called the ___________________ (they react together). The atoms on the right side of the arrow are the _______________________ (they are produced).

The numbers in front of the letters represent the number of molecules, while the subscripts or smaller numbers are the base and to the right stand for the number of atoms in that particular molecule.