General Science & Chemistry Flashcards
Define matter
everything around us that has matter and occupies space
Define elements
primary substances that all matter in the universe is composed of
Define atom
smallest piece of an element, simplest unit of matter
Define molecule
chemical structure composed of more than one atom
Define compound
a molecule that contains atoms of more than one element
Atomic symbol for Carbon
C
Atomic symbol for Hydrogen
H
Atomic symbol for Oxygen
O
Atomic symbol for Nitrogen
N
Atomic symbol for Calcium
Ca
Atomic symbol for Potassium
K
Atomic symbol for Chlorine
Cl
Atomic symbol for Magnesium
Mg
Describe calciums importance to the body
found in bones and teeth, important for membrane function, nerve impulses, muscle contraction, and blood clotting
Describe potassiums importance to the body
proper membrane function, nerve impulses, and muscle contraction
Describe chlorines importance to the body
membrane function and water absorption
Describe magnesiums importance to the body
required for activation of several enzymes
List the subatomic particles
protons, neutrons, and electrons
Define proton
positively charged atom particle found in the nucleus
Define neutron
particle with no electric charge found in the nucleus of an atom
Define electron
negatively charged particle that orbits the nucleus of an atom
Define atomic weight
average mass or weight of an atom
Define atomic number
number of protons in an atom
Define ion
atoms or molecules with a + or - charge; cations (+) and anions (-)
Define cation
an ion with a positive charge
Define anion
an ion with a negative charge
Describe ionic bond
a weak bond between a cation and an anion, attraction is the result of two molecules or atoms wiht opposite charges, ex. sodium chloride molecule
Describe covalent bond
strong bond comprised of molecules and atoms sharing electrons, ex. oxygen and hydrogen molecules
Describe polar covalent bonds
covalent bonds where one atom or molecule has a greater attraction to the other, resulting in electrons of the opposite atom or molecule spending more time on the other atom or molecule resulting in a negative charge, ex. water
Describe hydrogen bonds
the attraction of a hydrogen atom and a negatively charged atom in another molecule or at another site in the same molecule, ex. water molecule
Define chemical reactions
the breaking apart of bonds between atoms and rearranged into new combinations
Describe the importance of chemical reactions to the human body
they are necessary to sustain life
Define metabolism
all the chemical reactions in the body
Define work
movement or a change in chemical structure
Define energy
capacity to perform work
Define kinetic energy
energy of motion
Define potential energy
stored energy
Define decomposition reactions
breaking down a molecule into smaller fragments
Define synthesis reactions
assembles larger molecules from smaller components
Define catabolism
the breakdown of complex molecules within cells
Define anabolism
the synthesis of new compounds in the body
Describe the change in chemical reaction rates by temperature
increasing temperature increases reaction rates and conversly, lowering temperature slows reaction rates
Describe the change in chemical reaction rates due to partical size
smaller particles provide increased surface area for a given mass reslulting in a greater chance of collision of the reacting molecules speeding up the reactions
Describe the change in chemical reaction rates by catalysts
enzymes that increase the rate of chemical reactions without being used up in the process
Describe the change in chemical reaction rates due to concentration
increases the rate of chemical reactions
