Basic Chemistry

Matter is anything that takes up space and has mass.◦ Solid◦ Liquid◦ Gas

What is matter?

Energy is the ability to do work or to put matter into motion.◦ Kinetic energy- Movement◦ Potential energy- Stored energy

All living things are built of matter. Therefore in order to grow and function, they need a continuous supply of energy.

What is Energy?

In your groups try and list as many forms of energy as you can?

Also, give a list of any sources of energy.

Chemical energy◦ Energy stored in bonds of chemical substances◦ All body activities are done by chemical energy

Forms of Energy

Electrical energy results from the movement of charged particles.◦ In the body, an electrical current is generated

when charged particles move across cell membrane.

Forms of Energy

Mechanical energy◦ Directly involved with moving matter◦ Muscles in your body relax and contract to cause

movement.

Forms of Energy

Radiant energy travels in waves.◦ X-rays, infrared, visible light, radio, ultraviolet◦ Light energy stimulates retinas of your eyes to

produce vision.◦ Ultraviolet waves stimulate our bodies to produce

vitamin D.

Forms of Energy

In your groups, discuss any circumstances where one energy form is converted into another.

Electricity from socket is converted to light by lamp.

Chemical energy of ATP is converted to electricity of nervous system or mechanical energy of muscles.

Energy Form Conversions

No, energy cannot be created or destroyed.

Can energy be destroyed or created?

EFC are quite inefficient because some energy is always lost to the environment as heat.◦ Not lost but unusable

Energy Form Conversions

Atomic Structure, Molecules, and Compounds

The nucleus of an atom is made of protons and neutrons.

Proton is a tiny particle that has mass and a positive electrical charge

Neutron is a particle with approximately the same mass as a proton but with no charge.

Electron (e-) has little mass but has a negative electric charge.

The Atom

Draw and Label the structure of any atom.

On the periodic table, all elements are identified by one, two, or three letter abbreviations.

Atomic Symbol

The atomic number represents the number of protons found in that element’s nucleus.◦ Hydrogen atomic number = 1.◦ It has one proton in its nucleus

What does the atomic number represent?

The total number of protons and neutrons is equal to the mass number.◦ Electrons are too small to contribute to mass

number.

What is the mass number?

Isotopes are atoms of the same element have different mass numbers.◦ Different number of neutrons.◦ Cl-35 and Cl-37

What are isotopes?

Oxygen 65% Carbon 18.5% Hydrogen 9.5% Nitrogen 3.2% Other 3.9%

What are the four most common elements of the human body?

Atoms that gain or lose electrons have a net chemical charge and is called an ion.◦ Na+◦ Mg+2

◦ Si +4

◦ O-2

Ions

Molecules are formed when two or more atoms combine chemically.

H (atom) + H (atom) → H2 (molecule)

What is a molecule?

A Compound forms when two or more different atoms bind to form a molecule.

4H + C = CH4 (methane)

Compounds always have properties quite different from the atoms making them.

What is a Compound?

Chemical Bonds and Chemical Reactions

Electrons are distributed over one or more energy levels in a predictable pattern.◦ 1st inner most energy levels holds 2 electrons.◦ Each energy level afterwards holds 8 electrons.

Filling energy levels

Valence electrons are found on the outermost energy levels and determine the chemical behavior of the different elements.

What are valence electrons?

Ionic bonds form when electrons are completely transferred from one atom to another.

Example:◦ Na(+) + Cl(-) → NaCl

What is an ionic bond?

Covalent bonds occur when molecules share electrons.

For example:

Hydrogen atom + Hydrogen atom → Molecule of Hydrogen gas

What is a covalent bond?

Hydrogen bonds are weak bonds that form between polar hydrogen compounds.◦ Water’s high surface tension

Allows water strider to walk on water Help maintain structure of proteins

What is a hydrogen bond?

Hydrogen Bonding

Chemical reactions involve the making or breaking of bonds between atoms.

What is a chemical reaction?

Synthesis Reaction occur when two or more atoms or molecules combine to form a larger, more complex molecule.◦ Energy-Absorbing Reactions◦ Energy absorbed in bonds◦ Important for growth or repair of worn-out or

damaged tissue

A + B → AB

What is a Synthesis Reaction?

Decomposition Reactions occur when a molecule is broken down into smaller molecules.◦ Chemical energy is released as bonds break.◦ Digestion of food into their building blocks

AB → A + B

What is a Decomposition Reaction?

Exchange reactions occur when there is a switch made between molecule parts and different molecules are made.◦ Involves both synthesis and decomposition reactions◦ Occurs between ATP and glucose to produce ADP and

glucose-phosphate effectively trapping the glucose fuel molecule into the cell.

AB + C → AC + B or AB + CD → AD + CB

What is an Exchange Reaction?