(chemistry ) lect. test #1

Matter

Anything that has mass and occupies space

Element

Unique substances that cannot be broken into simpler substances by ordinary chemical methods

• unique properties: physical (senses and measurable), chemical (how atoms interact with one another )

Atom

Smallest particle of an element with properties of that element

Examples of the three states of matter within the human body

• Solid: bones

• Liquid: water

• Gas: oxygen

4 major elements of the human body

• make up 96.1%

C: carbon

H: hydrogen

O: oxygen

N: nitrogen

Subatomic particles of and atom

Proton: postive charge, is found inside the atoms “nucleus”

Neutron: has no charge, found within the atoms “nucleus”

Electron: has a negetive charge, found within orbital rings of the atom

Define molecule, explain difference between compound molecules and molecules of an element

Definition: two or more molecules bonded together (ex. 2 hydrogen, H2)

Compound includes different elements bonded together, while molecules only contain one type of element within the bond

Ionic and covalent bonds

Ionic:

• transfer of electrons from one atom to another atoms,

• held together by attraction between opposite charges

• Form ions, cation - element that has had its election taken away (positive), anion — element that received and electron (negetive)

Covalent bonding

• formed by the charging of two electrons

Hydrogen bonds

attractive forces between electro positive hydrogen of one molecule to an electronegative atom with another molecule

• acts as an intermolecular bond (binding within molecules)

Difference + Examples: non polar / polar bonds

Non polar

• molecules don’t have a charge, electrons are shared equally (linear molecule)

• - eg. CO2

Polar

• unequal charging of electrons, creasing a bond dipole…meaning one side is negetive while the other(s) are positive

• - eg. H2O

Cation and Anion

Cation: element that loses, making it more positive

Anion: element that gains an electron, making it more negetive

Catabolic

Decomposition

Eg. AB = A+ B

factors that change the rate of reactions

• temperature

• Concentration

• Particle size

• Catalyst

Anabolic

• smaller particles are bonded together to form larger more complex molecules

• Synthesis/ combination

Eg. A+B = AB

Exchange

• bonds are both made and broken

AB + C = AC + B

Element switch places

Metabolism

• sum total of all the chemical reaction occurring within the body cells