Chapter 2: Basic Chemistry Flashcards
Biological Organization from Smallest to Largest
- Atom
- Molecule
- Cell
- Tissue
- Organ
- Organ System
- Organism
- Species
- Population
- Community
- Ecosystem
- Biosphere
Atom
The smallest particle of an element that displays the properties of an element
Molecule
Union of two or more atoms of the same element; also the smallest part of a compound that retains the properties of the compound
Six Characteristics of Living Organisms
- Life is organized
- Life requires materials and energy
- Living organisms maintain homeostasis
- Living organisms respond
- Living organisms reproduce and develop
- Living organisms have adaptations
Levels of Classification From Least Inclusive to Most
Dear Kind Philip Came Over For Good Soup
- Species
- Genus
- Family
- Order
- Class
- Phylum
- Kingdom
- Domain
Acid
Molecules tending to raise the hydrogen ion concentration in a solution and thus to lower its pH numerically
Adhesion
Tendency of water molecules to form hydrogen bonds with polar surfaces, such as the inside of capillaries and transport vessels
Anion
Negatively charged ions that are formed from atoms or molecules that have more electrons than protons
Atomic Mass
Average of atom mass units for all the isotopes of an atom
Atomic Number
Number of protons within the nucleus of an atom
The equation to find Atomic Number
Atomic number=number of protons
Atomic Symbol
One or two letters that represent the name of an element
Base
Molecules tending to lower the hydrogen ion concentration in a solution and thus raise the pH numerically
Cation
Atom or group of atoms that bears a positive electric charge
Cohesion
Tendency of water molecules to cling to each other or to form hydrogen bonds with other water molecules
Covalent Bond
Chemical bond in which atoms share one or more pairs of electrons
Electron
Negative subatomic particle, moving about in an energy level around the nucleus of an atom that is considered to have no atomic mass units
Electronegativity
The ability of an atom to attract electrons toward itself in a chemical bond
Electron Shell
The average location, or energy level of an electron in an atom. Often drawn as concentric circles around the nucleus
Element
Substance that cannot be broken down into substances with different properties; composed of only one type of atom
Formula
A group of symbols and numbers used to express the composition of a compound
Hydrogen Bond
Weak bond that arises between a slightly positive hydrogen atom of one molecule and a slightly negative atom of another molecule or between parts of the same molecule
Hydrophilic
Water-loving; having an affinity for water; capable of interacting with water through hydrogen bonding
Hydrophobic
Water-fearing; lacking an affinity for water; insoluble in water; repelling water
Ion
An atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gathered one or more electrons
Ionic Bond
Chemical bond in which ions are attracted to one another by opposite charges
Hint: The names Bond… Ionic Bond. Taken, not shared.
Isotope
Atoms of the same element having the same atomic number but a different mass number due to a variation in the number of neutrons
Mass Number
Mass of an atom equal to the number of protons plus the number of neutrons within the nucleus
The Equation for Mass Number
Mass number=protons + neutrons
Matter
Anything that takes up space and has mass
Neutron
Neutral substance particle, located in the nucleus and assigned one atomic mass unit
Hint: Neutrons, neutral, nucleus
Nonpolar Covalent Bond
Bond in which the sharing of electrons between atoms is fairly equal
Octet Rule
The observation that an atom is most stable when its outer shell is complete and contains eight electrons; an exception is hydrogen, which requires only two electrons in its outer shell to have a complete shell
Polar Covalent Bond
Bond in which sharing of electrons between atoms is unequal
Proton
Positive subatomic particle located in the nucleus and assigned one atomic mass unit
Solute
Substance that is dissolved in a solvent, forming a substance
Solution
Fluid (the solvent) that contains a dissolved solid (the solute)
Solvent
Dissolves a great amount of substances especially those that are also polar
Valence Shell
The outer electron shell of an atom contains the valence electrons, which determine the chemical reactivity of the atom
Six Elements That Compromise 95% of Organisms Body Weight
Hint: Ninja CHOPS
- Nitrogen
- Carbon
- Hydrogen
- Oxygen
- Phosphorus
- Sulfur
Electronegativities of Six Elements
Nitrogen=3.0 Carbon=2.5 Hydrogen=2.1 Oxygen=3.5 Phosphorus=2.1 Sulfur=2.5
