Chapter 2 terms of "Life: The Science of Biology, 7th edition"
Terms
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- Mechanistic view
- The view that life is chemically based and obeys universal physicochemical laws
- The Hadean
- The 600 million years it took for the chemical conditions of Earth to become just right for life.
- The Archean
- The years in which life has existed.
- Nucleus
- The dense, positively charged center of an atom.
- Electron
- Negatively charged partical which orbit the nucleus and determines how atoms will interact in chemical reactions.
- Proton
- The positively charged unit in the nucleus that helps make up the mass of the atom
- Neutron
- A neutrally charged unit in the nucleus that helps make up the mass of the atom.
- Mass
- Measures the quantity of matter present.
- Atomic Mass Unit (amu)
- Dalton (Da)
- Element
- A pure substance that contains only one type of atom.
- Atomic Number
- The number of protons in an element's atoms.
- Mass Number
- The total number of protons and neutrons in the nucleus.
- Isotopes
- Differ in number of neutrons in the atomic nucleus from those atoms of the same element.
- Beta Particles
- Electrons
- Orbital
- The region of space where the electron is found at least 90% of the time.
- Electron Shells
- Energy Levels
- Molecule
- Two or more atoms linked by chemical bonds.
- Chemical Bond
- An attractive force that links two atoms together to form a molecule.
- Covalent Bond
- When two atoms attain stable electron numbers in their outermost shells by sharing one or more pairs of electrons.
- Molecular Weight
- The sum of the atomic weights of all atoms in the molecule.
- Electronegativity
- The attractive force that an atom exerts on electrons.
- Nonpolar Covalent Bonds
- This is produced when two atoms share electrons equally.
- Polar Covalent Bonds
- This is produced when two atoms don't share electrons equally- this happens because one of the atoms is more electronegative than the other.
- Polar Bond
- Opposite charges are seperated at the two ends, or poles, of the bond.
- Hydrogen Bond
- A weak bond, but when found in great numbers, they have considerable strength and greatly influence the properties of substances.
- Cations
- Positively charged ions.
- Anions
- Negatively charged ions.
- Complex Ions
- Groups of covalently bonded atoms that carry an electric charge.
- Ionic Bonds
- Bonds formed by electrical attraction between ions bearing opposite charges.
- Hydrophilic
- Water-loving. When a polar molecule interacts with water, it is hydrophilic.
- Hydrophobic
- Water-hating.
- Hydrocarbon Molecule
- A molecule containing only hydrogen and carbon atoms.
- Van der Waals Forces
- This results when two atoms of nonpolar molecules are in close proximity.
- Chemical Reaction
- This occurs when two atoms combine or change their bonding partners.
- Reactants
- The stuff you put together in a chemical reaction to attain the outcome.
- Products
- The outcomes of the chemical reaction.
- Energy
- The capacity to do work; the capactiy for change.
- Calorie
- The amount of heat energy needed to raise the temperature of 1 gram of pure water from 14.5ºC to 15.5ºC
- 1 Joule is = ______ cals
- .239 cals
- 1 cal is = _______ Joules
- 4.184 Joules
- Specific Heat
- The amount of heat energy required to raise the temperature of 1 gram of that substance by 1ºC.
- Solution
- Produced when a substance is dissolved in a liquide such as water.
- Solute
- The substance that is dissolved in liquid.
- Solvent
- The liquid that dissolves the solute.
- Qualitative Analysis
- Deals with substances dissoved in water and the chemical reactions that occur there. It also measures concentrations.
- Mole
- The amount of an ion or compound (in grams) whose weight is numerically equal to its molecular weight.
- Acids
- Release Hydrogen ions in a solution. A low pH is acidic.
- Bases
- Accept Hydrogen ions in a solution. A high pH is basic.
- Reversible Reaction
- This can proceed in either direction.
- Buffers
- Chemical mixtures that maintain a relatively constant pH even when substantial amounts of acids or bases are added.
- Functional Groups
- Consistently found together in a variety of different molecules.
- Isomers
- Molecules that have the same chemical formula but different arrangements of the atoms.
- Structural Isomers
- Differ in how atoms are joined together, producing compounds that have different chemical properties.
- Optical Isomers
- Occur whenever a carbon atom has four different atoms or groups attached to it.