Quiz 2 Flashcards
Define chemistry
The science of the structure and interactions of matter
Define matter
Anything that occupies space and has a mass
Define mass
The amount of matter a substance has
Define weight in relation to mass
Weight is the force of gravity acting on a mass
Define chemical elements
Building blocks of all matter living and nonliving
Define atoms
Smallest unit of matter that retains the properties and characteristics of that element
Atomic number
Number of protons in an element
Mass number
Sum of protons and neutrons in an element
Define atomic mass/weight
Average mass of all naturally occurring isotopes
Define isotopes
Atoms of an element that have different numbers of neutrons and therefore a different mass number
Define ion
An atom or molecule that gives up or gains an electron and therefore has a charge
Define compounds
Contains atoms of 2 or more different elements
Electrolytes
Ionic compound that breaks down into cations and anions in a solution
Octet rule
An atom needs 8 electrons in its valence shell to be stable. Atoms are more likely to interact if doing so will leaveboth valence shells with 8 elections
What makes noble gases special?
They are stable on their own because they have a full valence shell. They don’t need to bond.
Ionic bonds
Cations and anions attract each other due to the opposition of charges. Usually exist in solids. Found mostly in teeth, bones
Nonpolar covalent bonds
2 or more atoms share electrons evenly. Can form between atoms of the same or different elements. Can share up to 3 pairs of Valence elections
Polar covalent bonds
Electrons shared unevenly due to electronegativity. Nucleus of bigger atom attracts the shared electron more strongly so it becomes partially negative. The smaller electron becomes slightly more positive.
Electronegativity
The measure of an atom’s ability to attract shared elections to itself.
Hydrogen bonding
Weak bond that occurs due to the polarity of polar covalent bonds- not really a solid bond, more of an attraction.results from attraction of oppositely charged sharing of electrons
Free radical
Atom or group of atoms with an unpaired election in the outermost shell. Unstable, highly reactive, destructive to nearby molecules. Antioxidants inactivate them.
Radioactivity
When unstable atoms spontaneously break themselves down to reach a stable state. Breakdown causes radioactivity.
Half-life
Time it takes for half the atoms of a radioactive substance to break down into a more stable form.
Law of conservation of mass
Mass cannot be created or destroyed
Law of conservation of energy
Energy cannot be created or destroyed) only transferred
Potential energy
Energy stored by matter due to position (think holding up a ball)• static, waiting to be used.
Kinetic energy
Associated with matter in motion (think after you let go of the ball and it falls to the ground)
Exergonic reactions
Reactants start with energy and products have less energy after reaction (catabolic). Extra energy is released.
Endergonic reactions
Reactants start without energy and products gain energy (anabolic). Energy is required for the reaction. Absorb more energy than is released.
Metabolism
The sum of all chemical reactions in the body. Coupling of exergonic and endergonic reactions - energy released from exergonic usually used to drive endergonic.
Activation energy
Energy required for a reaction to occur. Reactions depend on concentration and temperature. High concentration of atoms means there are more atoms available to bond. High temperature makes atoms more around a lot, increasing likelihood of forming bonds.
Catalysts
Help speed up reactions by lowering amount of activation energy needed to start a reaction. Ex. Enzymes in the body.
Synthesis
Chemical reaction where the resulting product is bigger than the reactants. Bonds formed. Anabolism. Usually endergonic.
Decomposition
Chemical reaction where resulting products are smaller than reactants. Bonds broken. Aka catabolism. Usually exergonic.
Exchange reactions
Ab+cd = ad + BC
Reversible reactions
Ab ←→ a+b
Inorganic vs. Organic compounds
Inorganic usually doesn’t contain carbon. Organic always has carbon, usually hydrogen and always covalent bonds. Organic compounds are more complex.
H2O has polarity. T/f
True
Hydrolysis
Breakdown of large molecules into simpler ones with H2O
Dehydration synthesis
2 simple molecules join together, eliminating H2O in the process.
Dehydration synthesis vs. Hydrolysis
H20 is the product in dehydration synthesis, but the reactant in hydrolysis
Ionization
The process by which ions are formed by gain or loss of an electron from an atom or molecule.
Hydrophilic
Dissolves in H20. Has polar covalent bonds.
Hydrophobic
Not water soluble
Mixture
Combo of elements or compounds physically blended together but not bound by chemical bonds.
Solutions
Solutes mixed into a solvent are evenly distributed (transparent)
Colloids
Size of particles of solvent larger than in a solution so it is opaque. Ex. Milk
Suspension
Suspended material may mix at the beginning but will settle out. Ex. Muddy water.
Concentration
How much solute is found in the solvent. Moles per litre (moL/L) = morality
Acid
Proton donor, pH below 7
Base
Proton acceptor. pH above 7
Salt
Electrolytes- acids and bases react to form salts.
Buffer systems
Used to convert strong acids and bases into weaker ones. they remove or add protons.
Carbohydrates
Function mainly as a source of chemical energy for generating ATP. Formed via carbon, hydrogen, oxygen.
2:1 H:O. 1 H2O per C. sugars, glycogen, starches, cellulose
3 major groups of carbs
Monosaccharides, disaccharides, polysaccharides
what are simple sugars made up of
monosaccharides and disaccharides (combo of 2 monosaccharides through dehydration synthesis). end in -ose.
characteristics of simple sugars
can be absorbed without need to digest further. use hydrolysis to break down disaccharides and polysaccharides
how are saccharides joined together
dehydration synthesis
polysaccharides
- many monosaccharides joined together through dehydration synthesis
- glycogen is the main one found in the body. - hydrolysis can break them down into monosaccharides.
- found in starches
where in the body is glycogen stored
liver and skeletal muscle
what is the storage form of glucose in the body
glycogen
