1. Chemistry of Life
chapter 2
• Atoms - the basic unit of
matter
• Made up of 3 parts

2. Atomic structure
• Protons (+) charge
• Neutron (0) charge
• Electrons (-) charge

3. Element
• A pure
substance that
consist only
one type of
atom
• EX: C,H,O,N

4. ISOTOPES
• Atoms of the
same element
that have
different # of
neutrons

5. 28 1. Atomic #
Ni 2. Element symbol
Nickel 3. Name of atom
4. Average atomic mass
58.71

6. Compound
• A substance
formed when two
or more elements
combine in a
definite
proportions

7. Figuring out atomic structure
How many protons, electrons, &
neutrons does carbon have?

8. Carbon
• Atomic number = 6 • Atomic mass = 12
• (round atomic number to a whole #)
• To calculate # of
• Carbon will have 6
neutrons:
protons & 6 electrons
• Atomic mass 12
• - atomic # -6
• = neutron # 6

9. Lets try one more
• Find the # of protons, • Chlorine:
electrons, & neutrons • Atomic # is 17,
for chlorine • It has 17 protons & 17
electrons
• Atomic mass 35
• Atomic # -17
neutron # = 18

10. Molecules and Bonding
• more ways to view molecules

11. Chemical BONDS!
• Chemical Bonds: Are the electrical forces
linking atoms.

12. Molecules and Bonding
Two Types!
•Covalent Bonds: Are characterized by the
sharing of pairs of electrons between atoms.

13. Molecules and Bonding
Two Types!
•Ionic Bonds: Are characterized by the
Stealing or Giving of electrons between
atoms.

14. Molecules and Bonding

15. Molecules and Bonding
• How many bonds can an element make?
Count the
bonds for
Carbon!

16. Properties of Water
• Water is a Polar Molecule
• Uneven Electrical Charge

17. Properties of Water
• Water is essential for life!!!
• 78% of the body is made up water
• It is the universal solvent
• The body’s chemical reactions require
water!