Name: ____________________ Period:_____ Chapter 2 Notes: The Chemistry of Life Words to Know: atom, nucleus, protons, neutrons, electrons, element, isotopes, compound, ionic bond, covalent bond, molecule, hydrogen bond, solution, solute, solvent, acids, bases, buffers, pH, monomers, polymers, carbohydrates, monosaccharides, disaccharides, polysaccharides, lipids, fatty acids, glycerol, saturated fat, unsaturated fat, nucleic acids, nucleotides, proteins, amino acids, chemical reaction, reactants, products, activation energy, catalyst, enzymes, substrates, dehydration synthesis, hydrolysis, active site, lock‐and‐key model, organic The Nature of Matter Atom: The smallest _________________________ of an element that has the _________________________ properties of the element. 
Three subatomic particles:  Protons: _________________________  Neutrons: _________________________  Electrons: _________________________; in constant _________________________ around the nucleus 
# protons = # electrons, so the atom is _________________________ overall. Element: A pure substance that consists entirely of one type of _________________________. 
Listed on the _________________________. 
Ex: hydrogen (H) Isotope: Contain same number of protons & electrons (so are the same element), but have a differing number of _________________________.  Ex: carbon‐12 & carbon‐14 Compounds: Two or more elements _________________________ combined together. 
The chemical and physical properties of a compound are _________________________ than the properties of the individual _________________________ from which it is formed. 
Ex: NaCl 1 Chemical Bonds 
Two types: 
Ionic: Electrons are _________________________ from one atom to another; creates ions ▪
Ions: _________________________ atoms ▪
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Ex: Na+, Cl‐ Covalent: Electrons are _________________________ (travel around both nuclei); creates molecules ▪
Molecules: smallest _________________________ of a compound ▪
Ex: H2O (_____ atoms of H, _____ atom of O) Properties of Water Mixture: Composed of _________________________ or more elements or compounds. 
_________________________ chemically combined. Solution: a _________________________ with components evenly distributed throughout 
Two parts: Solute: the part that is _________________________ Solvent: the part that is _________________________ Acids: form _________________________ ions in a solution 
pH = 1‐7 Bases: form _________________________ in a solution 
pH = 7‐14 Buffers: weak acids or bases that react with strong acids or bases to _________________________ sudden changes in pH 
Help maintain _________________________! 2 Carbon Atoms Why is Carbon in all life? 
Carbon has _____ electrons for bonding, so it can form strong covalent bonds with many other elements (like H, O, P, S, and N). 
Carbon can form single, double and triple bonds with _________________________. 
Organic = contains _________________________ Macromolecules = _________________________ molecules 
Monomers: _________________________ unit 
Polymers: _________________________ compound 
Types of Macromolecules: carbohydrates, lipids, nucleic acids, proteins Macromolecule Chemical Composition ‐ C, H, O Carbohydrates Lipids Nucleic Acids ‐ C, H, O ‐ Glycerol + fatty acid Examples Function in Living Things ‐ monosaccharides: _____________________ sugars ( glucose, fructose, galactose) ‐ polysaccharides: _____________________ sugars (glycogen, starch) ‐ fats, oil, waxes ‐ saturated: all _____________________ bonds (animal fats = bad!) ‐ unsaturated: at least one _____________________ bond (vegetable fats = good!) ‐ Main source of _______________________. ‐ Structural purposes in some cells (_______________________ in plants). ‐ DNA, RNA ‐ C, H, O, N, P ‐ sugar + phosphate group (P) + nitrogenous base (N) ‐ polymers of ______________
______________ ‐ _______________________ energy. ‐ Membranes & waterproof coverings. ‐ Chemical ________________________ (steroids). ‐ Store & transmit _______________________. 3 ‐ ‐ C, H, O, N, S _____________________ ‐ polymers of ______________ ______________ Proteins ‐ Control ________________________ (enzymes) & cell processes. ‐ Transport materials in & out of cells. ‐ Fight disease (______________________). Chemical Reactions & Enzymes Chemical Reactions: one set of chemicals _________________________ into another set of chemicals 
CO2 + H2O  H2CO3 Chemical reactions always involve the _________________________ of bonds in the reactants and the _________________________ of new bond in the products. CO2 + H2O  H2CO3 Reactants: elements or compounds that _________________________ into a reaction 
Ex: CO2 & H2O Products: elements or compounds that are _________________________ by a reaction 
Ex: H2CO3 Atoms and Chemical Reactions 2HCl + 2Na ‐> 2NaCl + H2 
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Remember the 2 after H2, means that there are _____ atoms of H in this molecule. (For H2O, there are _____ atoms of H and _____atom of O.) 
The 2 in front of 2HCl, means that there is 2 of the _______________ molecule, so 2 atoms of H and 2 atoms of Cl. Reactions that release energy often occur _________________________. Reactions that absorb energy will not occur _________________________ a source of energy. Activation Energy: the _________________________ needed to get a reaction started Catalyst: a substance that _________________________ up the rate of a chemical reaction by lowering the activation energy. 4 Enzymes: _________________________ that act as _________________________ in cells. Substrates: the _________________________ of an enzyme‐
catalyzed reaction Active site: the spot on the enzyme where the substrate_________________________  _________________________, pH and regulatory molecules can affect the activity of enzymes. Two Special Types of Reactions Dehydration Synthesis: two molecules bond together & H2O is ________________________. Hydrolysis: H2O is used to _______________________ two molecules. 5