essential chem (1-18) Flashcards
contrast the term element with compound: an element is a … substance composed of …. that cannot be …. whereas a compound is composed of … and can be …
pure; one type of atom; broken down; two or more elements; broken down
(symbols and charges) carbon
C; 4-
(symbols and charges) hydrogen
H; 1+
(symbols and charges) oxygen
O; 2-
(symbols and charges) nitrogen
N; 3-
(symbols and charges) phosphorus
P; 3-
(symbols and charges) sulfur
S; 2-
nucleus: small … region in … of atom
positively charged; center
proton: …. charged atomic particle, located in …
positively; nucleus
neutron: electrically … particle in atomic …
neutral; nucleus
electron: …. charged particle located in …. that surround the …
negatively; orbitals; nucleus
electron density: region of …. where electron is located
probability
(contrast the atomic mass and atomic number) Atomic mass is the mass of a single … of an element that is nearly equivalent to the total number of …. and … in the nucleus, whereas the atomic number is the number of … in an atom
isotope; protons; neutrons; protons
(what is the difference between the terms atomic mass and atomic weight) atomic weight takes into consideration the masses of …. where the atomic mass does not
all the isotopes of an element
(what is an isotope and what is “special” about radioactive isotopes) an isotope is an atom of an element that contains a different number of …. radioactive isotopes have …. due to an unfavorable ratio of …. For radioactive isotopes, the … changes and the isotopes … into a different …
neutrons; unstable nuclei; nucleic particles; atomic mass; decay; form
(what determines interactions between atoms? why are valence electrons important?) interactions are determined by the number of ….. They are important because they are the electrons through which …. are formed, and they determine if an element acts as a … or an …
valence electrons; chemical bonds; cation; anion
chemical bond: an … between atoms entailing the sharing or taking of …. that … atoms together
attraction; valence electrons; binds
covalent bond: a bond in which atoms … electrons
share
single bond: a bond in which … of electrons are shared between atoms
one pair
double bond: a bond in which … of electrons are shared between atoms
two pairs
electronegativity: the ability of an atom to … the electrons of an …
attract; adjacent atom
nonpolar covalent bond: a covalent bond in which electrons are shared …
equally
polar covalent bond: a covalent bond in which electrons are shared … due to differing …. of the bonding atoms
unequally; electronegativities
(what is the difference between a structural and molecular formula) a structural formula indicates the … of bonds and the … of a molecule’s atoms through the use of …. A molecular formula, however, gives information concerning the … and … of atoms in a molecule
number; arrangement; dashes; numbers; types
oxygen gas
O2
Carbon dioxide
CO2
glucose
C6H12O6
phosphate
PO4 3-
Ammonia
NH3
Water
H2O
(How do ionic bonds compare with covalent bonds) an ionic bond occurs due to … between positively and negatively charged ions and entails the … and … of electrons. Howeer, covalent bonding merely entails the …. of electrons
electrostatic; loss; gain; sharing
(compare and contrast hydrogen bonds and van der Waals interactions) hydrogen bonds are stronger intermolecular forces that occur when hydrogen is bonded with a highly …. and then bonds with another on an ….. Van der Waals forces, however, are weaker and are based on …. that can, in some cases, occur in all molecules (e.g.. ….)
electronegative atom; adjacent molecule; dipoles; induced dipoles
(dynamic chemical equilibrium) dynamic chemical equilibrium is a state in which the rate at which products are formed is equal to the rate at which
the reverse reaction occurs, where the products reform reactants
water is polar due to the presence of … that results from the … of electrons located on the oxygen atom
dipoles; lone pairs
(property and relation to water) cohesion: a molecule’s attraction toward molecules of the ….
cohesion in water occurs due to the fact that water molecules undergo …, which are strong intermolecular forces. through hydrogen bonding, the positively charged hydrogens on one water molecule bond with the …. on adjacent water molecules
same identity; hydrogen bonding; negatively charged oxygens
(property and relation to water) adhesion: a molecule’s attraction toward particles of a … The hydrogens on water bond …. on an adjacent molecule and the oxygen bonds with a ….
different substance; with negatively charged ions; positively charged ion
(property and relation to water) surface tension: phenomenon through which … forces cause a liquid to adopt a …. so as to minimize …. Measures the energy required to increase a liquid’s …
surface tension in water occurs as a result of hydrogen bonding. the molecule’s at the water’s surface are …. to those below it, resulting in the spherical shape
cohesive; spherical; surface area; surface area; unequally attracted
(property and relation to water) high specific heat: large amount of heat needed to raise the temperature of a … sample of a material by … The heat absorbed by water molecules is utilized as an …. to break the bonds and eventually increase the kinetic energy of the water molecules sufficiently so that they change state. however, due to the strength of water’s hydrogen bonds, a …. is necessary to … the bonds. Consequently, water tends to be more … to temperature changes and thus has a high specific heat
1 g; 1 K; energy source; large amount of heat; break; resistant
(property and relation to water) heat of vaporization: amount of heat required for a liquid to …
become a gas
(property and relation to water) evaporative cooling: process by which the evaporation of a liquid …
when water vaporizes, it makes use of the … that is available in its surroundings. it … this heat, which resultls in a lowered …
lowers temperatures; energy as heat; absorbs; atmospheric temperature
(what is special about water and density) contrary to most substances, water is … dense in the solid state than in the liquid state
less
(phenomena and properties of water) during the winter, air temperatures in the northern United States can remain below 0 degrees C for months, however animals in the lake survive:
ice less dense than water; high specific heat
(phenomena and properties of water) many substances–for example, salt and sucrose,— dissolve quickly in water
polarity; water as “universal solvent”
(phenomena and properties of water) when you pour water into a 25-ml graduated cylinder, a meniscus forms
adhesion
(phenomena and properties of water) sweating and the evaporation of sweat from the body surfacing helping to reduce a human’s body temp
evaporative cooling
(phenomena and properties of water) water drops that fall on a surface tend to form rounded drops or beads
cohesion and surface tension
(phenomena and properties of water) water drops that fall on your car tend to bead or round up more after polishing
stronger cohesive forces indicate hydrophobic polish
(phenomena and properties of water) if you touch the edge of a paper towel to a drop of colored water, the water will move up into (or be absorbed by) the towel
adhesion, capillary action
solute: substance that
dissolves
solvent
dissolving medium
aqueous solution: a solution consisting of a substance
dissolved in water
hydrophilic:
favors and interacts with water
hydrophobic
repels water
molarity: measure of ….; … solute/ … solution
concentration; moles; liters
hydroxyl causes organic compounds to be more …, forms … bond and is …., present in … and some …
soluble; hydrogen; polar; sugars; amino acids
carbonyl: increases …., …, present in …
melting/boiling pts; polar; sugars
carboxyl: …, acts as an … and is present in a large number of …. molecules including … and …
charged; acid; biological; fatty acids; amino acids
amino: acts as a …, …, included in … which form …
base; charged; amino acids; proteins
sulfhydrl: aid in …, … present in some …, forms … bonds
stabilizing proteins; polar; amino acids; disulfide
phosphate: …, acts as an …., capable of transferring … between .. molecules, ….
charged; aacid; energy; organic; polar
(functional groups) when a functional group attaches to a …, it changes some …, determines the … and … a molecule will undergo
hydrocarbon; properties; polarity; type of reaction