Chapter 2 Chemistry of Life

Composition of Matter Matter- anything that has mass and takes up space. Mass- measure of the amount of matter in an object. DOES NOT CHANGE

What is an atom?!?! The simplest particle of an element That retains all of the properties of that element.

Proton: Neutron: Electron: What makes up an atom? Located inside the nucleus Neutron: Located inside the nucleus Electron: Located outside the nucleus in an electron cloud.

Proton Neutron

Periodic Table of Elements

ELEMENTS- substances that cannot be broken down chemically into simpler kinds of matter Atomic number Chemical symbol Atomic mass

# of electrons = # of protons Atomic Number: the number of protons in the nucleus - appears above the chemical symbol. Mass Number: equal to the total number of protons and neutrons in an atom. # of electrons = # of protons

# of Neutrons = 19-9 # of Neutrons = 10 Atomic Number Mass Number # of Neutrons = Mass Number – Atomic Number # of Neutrons = 19-9 # of Neutrons = 10

Proton Neutron Electron Proton Neutron Electron

Compound- is a substance made of the joined atoms of two or more different elements. Molecule- group of atoms held together by covalent bonds.

Chemical Bonds Covalent bond- 2 or more atoms share electrons. Hydrogen bond- attraction between two water molecules. Ionic bond- unequal sharing of electrons-

Ion Has gained or lost an electron. Positive or negative charge.

Water 70 % of your body is made of water. Water absorbs heat more slowly than other substances. Water retains energy longer than other substances.

Cohesion Attraction between substances of the same kind. Water bonding with water.

Adhesion Attraction between different substances. Water bonding to a leaf.

Solution Mixture in which one or more substances are evenly distributed in another substance. Ex: sugar and water

Polarity Water is a polar molecule. Polar molecules dissolve in water. Like dissolves like Nonpolar molecules do not dissolve well in water. Oil- clumps together in water

pH Acid- (0-6) form hydrogen ions (H+) Base-(8-14) form hydroxide ions (OH-) Neutral- (7)

Carbohydrates Organic compounds made of carbon, hydrogen, and oxygen atoms in the proportion 1:2:1. Monosaccharides- building blocks of carbohydrates. Simple sugars Glucose

Lipids Nonpolar molecules that are not soluble or mostly insoluble in water. Fats, phospholipids, steroids, & waxes. Lipids are important in the cell membrane. phospholipid bilayer Fats are lipids that store energy.

Proteins Large molecules made of amino acids. Structural functions & enzymes in reactions

Nucleic Acids Long chain of smaller molecules called nucleotides. Sugar Base Phosphate group DNA- 2 strands of nucleotides that spiral around each other. RNA- one single strand of nucleotides or of base-paired nucleotides.

ATP Adenosine triphosphate Cells need a steady supply of ATP to function.

Ability to move or change matter. Light, heat, chemical, mechanical, and electrical. Energy can be stored or released during chemical reactions.

Energy Reactants  products

Enzyme Substances that increase the speed of chemical reactions. Most are proteins. Help organisms maintain homeostasis. CO2+ H2O  H2CO3

Enzyme Specificity Substrate- substance on which an enzyme acts during a chemical reaction. active sites- folds on an enzyme.