AP Biology Essential Chemistry – Flashcards
Unlock all answers in this set
Unlock answersquestion
Contrast the term element with compound
answer
An element can't be broken down into simpler substances. A compound is formed from 2 or more elements bonded together
question
Carbon
answer
C, + - 4
question
Hydrogen
answer
H, + -1
question
Oxygen
answer
O, -2
question
Nitrogen
answer
N, -3
question
Phosphorus
answer
P, -3
question
Sulfur
answer
S, -2
question
Contrast the terms atomic mass and atomic number.
answer
The atomic mass is the total sum of the number of neutrons and protons. The atomic number is the number of protons in the nucleus.
question
What is the difference between the terms atomic mass and atomic weight?
answer
Atomic weight is the average mass of atoms of an element. Atomic mass is the number of neutrons and protons combined.
question
What is an isotope and what is special about radioactive isotopes?
answer
An isotope is any two chemical elements that have the same atomic number, but different atomic weights. Radioactive isotopes decompose by producing a helium or electron nucleus causing nuclear composition stability.
question
What determines interactions between atoms? Why are valence electrons important?
answer
The interactions are determined by the number or electrons in the valence shell, which affects chemical behavior. Valence electrons are important, because the determine if the atom will gain electrons or give them away.
question
Chemical bond
answer
An attraction between two atoms built by sharing outer-shell electrons or the existence of opposite charges
question
Covalent bond
answer
A bond is in which atoms share pairs of electrons
question
Single bond
answer
a chemical bond in which two atoms share a pair of electrons
question
Double bond
answer
a bond in which two atoms share two pairs of electrons
question
Electronegativity
answer
the measure of the need of an atom to attract a bonding pair of electrons
question
Nonpolar covalent bond
answer
a type of bond that happens when two atoms, with similar electronegativity, share a pair of electrons
question
polar covalent bond
answer
a covalent bond between atoms that differ in electronegativity. The electrons are pulled closer to the greatest one, causing a (-)and a (+)
question
What is the difference between a structural and molecular formula?
answer
Molecular formulas portray what atoms are being used and the quantity. Structural formulas portray what types of bonds and a graphic representation.
question
Oxygen gas
answer
O2
question
Carbon Dioxide
answer
CO2
question
Glucose
answer
C6H12O6
question
Phosphate
answer
PO43-
question
Ammonia
answer
NH3
question
Water
answer
H20
question
How do ionic bonds compare with covalent bonds?
answer
Ionic bonds consist of electrons being taken away from an atom and given to another. In covalent bonds electrons are shared.
question
Compare and contrast hydrogen bonds and van der waals interactions.
answer
A hydrogen bond is a weak bond with one electronegative atom, a hydrogen atom, and another electronegative atom. Van der waals interactions is the force between two or more non polar molecules. They're alike because they contain intermolecular forces. They differ because van der waals interactions can be strong, while hydrogen bonds cannot.
question
Define a dynamic chemical equilibrium in terms of quantities of reactants and products.
answer
A chemical equilibrium is where the reactions equal each other exactly. The amount of products do not have to be equal, but must have a stabilized ratio. The reactions should equal each other out, the quantities should be in a ratio where the products leftover shouldn't be greater or lesser that the original matter.
question
Why is water considered a polar molecule?
answer
A polar molecule is a molecule in which the centroids have different charges. Water's opposite ends are different charges.
question
Cohesion
answer
the bonding together of like molecules;In liquid form hydrogen is very fragile, causing reformation. All H20 molecules bond to their neighbors, staying together
question
Adhesion
answer
the attraction between different kinds of molecules. Water has the ability to cling or connect itself to other substances due to polarity.
question
Surface tension
answer
a measure of how difficult it is to break the surface of a liquid. Between air and water hydrogen bonds tougher and to water below creating an illusion of an invisible film.
question
High specific heat
answer
the amount of heat that must be absorbed for 1g of a substance to change temperature by 1 degree celsius. Water has the ability to stabilize its own temperature. It can also resist changing temperature by absorbing or releasing heat. Heat must be absorbed to break hydrogen and vice versa
question
Heat of vaporization
answer
the amount of heat a liquid must absorb for 1 g of it to turn gaseous. Water requires a high level of heat, because the hydrogen bonds must be broken before molecules release
question
Evaporative cooling
answer
The property of a liquid where the surface becomes cooler evaporation , losing highly kinetic molecules to a gaseous state; contributes to the stability of temperature
question
Solute
answer
The substance that is dissolved
question
solvent
answer
the dissolving agent of the solution, or the dissolver
question
aqueous solution
answer
a solution in which water is the solvent
question
hydrophilic
answer
having an infinity for water, or "liking" it
question
hydrophobic
answer
having an aversion for water, or "fearing" it
question
molarity
answer
a common measure of solute concentration, referring to the number of moles of elute per liter of solution
question
What defines an acid and a base?
answer
An acid is a substance that increases the hydrogen ion concentration of a solution. A base is the opposite. It reduces the hydrogen ion concentration in a solution.
question
Why are small changes in pH so important in biology?
answer
pH levels in the environment verify which types of planets and animals species can live in that area.
question
What is a buffer? Give an example on how they would work in a living organism.
answer
Buffers are substances that minimize the changes in the concentrations of H+ and OH- in a solution. Carbonic and buffers regulate our blood's pH level. It can give away H+ if there are too many OH- in the blood and vice versa.
question
What is acid precipitation and why is it important to living organisms?
answer
Rain, snow, or fog with a pH lower or more acidic than 5.6. The acid rain pollutes the environment and slows down growth.
question
Why is organic chemistry so important in the study of biology?
answer
Organic chemistry is the study of structure, properties, and reactions of organic compounds. Most reactions in biology are organic and organic chemistry is linked to compounds produced by living organisms. Biology is the study of life.
question
What is special about carbon that makes it the central atom in the chemistry of life?
answer
Instead of Carbon becoming an ion, it shares its electrons with other atoms, making it the central point where molecules can branch off. While also holding a chemical bond.
question
Structural
answer
Differ in covalent partners, have same molecular formula, differ in arrangement, differ in location of double bonds
question
Geometric
answer
same number and types of atoms and bonds, differ in spatial arrangements, creates geometric structure
question
Hydroxyl
answer
Also known as alcohols or phenols;it's polar from electronegative oxygen atoms drawing electrons towards itself; attracts water molecule helping it dissolve organic compounds like sugars
question
Carbonyl
answer
Also known as ketones or aldehydes; structural isomers with different properties as for acetone and propanol; making molecules water-soluble; all sugar molecules have one carbonyl group
question
Carboxyl
answer
known as carboxylic acids or organic acids; a source of hydrogen ions;covalent bond between oxygen and hydrogen so polar, hydrogen ions dissociate reversibly
question
Amino
answer
known as amines;made of nitrogen atom bonded to two hydrogen atoms; compounded with carboxylic acids create amino acids;they can pick up proteins from acids
question
Sulfhydryl
answer
known as thios;made of sulfur bonded to a hydrogen atom;stabilize proteins
question
Prosphate
answer
Known as organic phosphates;built out of a phosphate atom single-bonded to three oxygen atoms and double-bonded to another; key parts of energy molecules;they're attached to become anions; phosphate groups are acidic
