Chemistry final review rev1
Law of Conservation of Mass
Matter can neither be created nor destroyed and that The total mass of products is equal to the total mass of reactants.
Barometer
Measures the pressure exerted by the gases in the atmosphere by the height of mercury in the column (mmHg). *The pressure exerted by the gases in the atmosphere is equal to the downward pressure of a mercury column in a closed glass tube.
a compound's empirical formula is N2O5, if the formula mass is 108 amu, what is the molecular formula
N2O5
Electrons have what type of charge?
Negative
Neutrons have what type of charge?
Neutral (or no charge)
Non-redox
No electron transfer is involved
Chemical change
Occurs when a substance is converted into one or more new substances. a change in color, the formation of a solid (precipitate), the formation of bubbles (gas) heat (or flame) produced or heat absorbed
Single-Replacement reactions
One element takes the place of a different element in a reacting compound A+BC -> AC+B
Decomposition reactions
One substance splits into two or more simpler substances. AB -> A+B
OIL
Oxidation Is the Loss of electrons
Ideal gas law formula
PV = nRT
what is the formula for Lead IV oxide?
PbO2 (ionic)
Protons have what type of charge?
Positive
RIG
Reduction Is the Gain of electrons
what is the formula for sulfur dichloride
SCl2
what is the empirical formula for a compound that is 53.3% O and 46.7% S
SO2
Weak electrolytes
Solutes that only partially dissociate when dissolved in water
Strong electrolytes
Substances that dissolve well in solution
Solubility
The amount of solute that dissolves in a solution; may also refer to how quickly a solute dissolves in a solution (i.e. the dissolvent rate) affected by the type of solvent and temperature expressed as grams of solute per 100 grams of solvent (usually water) solubility=grams of solute/grams of liquid (water in most cases)
Exothermic
The energy of the reactants is greater than that of the products and heat is released along with the products -the heat of reaction (ΔH) value is written with a negative sign (-) indicating heat is released.
Endothermic
The energy of the reactants is lower than that of the energy of the products -heat is absorbed and used to convert the reactants to products and written with a (+) sign.
Molar Mass (definition)
The mass of one mole of a substance. the number of grams that equals the atomic mass of that element
Orientation
The reactants must align properly to break and form bonds.
Double-Replacement reactions
The two positive ions in the reacting compounds exchange places AB+CD -> AD+CB
Excess reactant
What's left over.
what is the formula for zinc flouride
ZnF2
write the noble-gas electron configuration represented in the orbital diagram below
[Ne] 3s2 3p3
write the noble gas electron configuration for silicon
[Ne]3s2 3p2
the elements in group 1 are also known as the
alkali metals
Name the compound Al2S3.
aluminum sulfide
a species that can react as either an acid or a base is...
amphoteric
a negative ion is known as an
anion
evidence gathered sine mendeleev's time indicates that a better arrangement than atomic mass for elements in the periodic table is an arrangement by
atomic number
What is an isotope?
atoms of the same element with different numbers of neutrons
the melting points of ionic compounds are higher than the melting points of molecular compounds because
attractive forces between ions are greater than the attractive forces between molecules
the atomic mass of an element listed in the periodic table is the
average atomic mass
what did Arrhenius theorize?
bases give OH- and acids give H+ (H3O+)
A liquid reaches its boiling point when its vapor pressure...
becomes equal to the external pressure.
what are properties of bases?
bitter, slippery, pH of <7, turn indicators blue
name the compound CF4
carbon tetraflouride
a positive ion is known as a
cation
covalent bond
chemical bond that forms when 2 atoms share electrons
ionic bond
chemical bond that occurs when an atom transfers an electron to another atom
what do you use to balance chemical equations?
coefficients
name the compound CuO
copper II oxide (ionic)
the chemical bond formed when two atoms share one or more pairs of electrons is a
covalent bond
in a row in the periodic table, as the atomic number increases, the atomic radius generally
decreases
Name the compound N2O3
dinitrogen trioxide
what is the name of N2O3?
dinitrogen trioxide (covalent)
what are shared in a covalent bond
electrons
What is an electron cloud?
electrons moving at high speed; small negatively charged particles
a formula that shows the simplest whole-number ratio of the atoms in a compound is the
empirical formula
the main energy level that can hold only two electrons is the
first
what is the sum of the atomic masses of all the atoms in a formula for a compound
formula mass
what happens when acids react with metals?
gives off H2 gas
if electrons in an atom have the lowest possible energies the atom is in the
ground state
compared with ionic compounds, molecular compounds
have lower melting points
ionic compounds are brittle because the strong attractive forces
hold the layers in relatively fixed positions
what does supersaturated mean?
holds more solute than it can (saturated then heated up and more solute added)
what relationship between pressure and volume does Boyle's Law demonstrate?
inverse
the B--F bond in BF3 (electronegativity for B is 2.0; electronegativity for F is 4.0) is
ionic
the empirical formula is always the accepted formula for an
ionic compound
Activation energy
is the amount of energy required to break the bonds between atoms of the reactants
Heat of reaction
is the amount of heat absorbed or released during a reaction
Actual yield
is the amount of product obtained when the reaction takes place.
Theoretical yield
is the maximum amount of product, which is calculated using the balanced equation.
Atmospheric pressure
is the pressure exerted by a column of air from the top of the atmosphere to the surface of the Earth.
Percent yield
is the ratio of actual yield to theoretical yield.
how does the energy required to remove an electron from an atom change as you move left to right in period 4 from potassium through iron
it generally increases
temperature is the measure of...
kinetic energy (motion)
in drawing a lewis structure, the central atom is generally the
least electronegative atom
the quantum number that indicates the position of an orbital about the three axes in space is the
magnetic quantum number
atoms of the same element can differ in
mass number
Law of conservation of mass
mass of reactants=mass of products
isotopes are atoms of the same element that have different
masses
what is an ionic compound made up of?
metal and non-metal
the molar mass of an element is the mass of one
mole of the element
which of the following shows the types and numbers of atoms joined in a single molecule of a molecular compound
molecular formula
what does unsaturated mean?
more solute can still be added
the average atomic mass of an element is the average of the atomic masses of its
naturally occurring isotopes
a nuclear particle that has about the same mass as a proton, but with no electrical charge, is called a
neutron
if two covalently bonded atoms are identical, the bond is
nonpolar covalent
the chemical formula for an ionic compound represents the
number of atoms in each molecule
A chemical formula includes the symbols of the elements in the compound and subscripts that indicate
number of atoms or ions of each element that are combined in the compound
the periodic law states that the properties of elements are periodic functions of their atomic numbers. What determines the position of each element in the periodic table
number of protons
all isotopes of hydrogen contain
one proton
a three-dimensional region around a nucleus where an electron may be found is an
orbital
the electron configurations of the noble gases from neon to radon in the periodic table make these elements part of the
p block
the set of orbitals that are dumbbell shaped and directed along the x, y, and z axes are called
p orbitals
a horizontal row of blocks in the periodic table is called a
period
the electron configuration of cesium, atomic number 55, is [Xe] 6s1. In what period is cesium
period 6
if the atoms that share electrons have an unequal attraction for the electrons, the bond is called
polar
elements in a group or column in the periodic table can be expected to have similar
properties
Nucleus contains what subatomic particles?
protons neutrons
An uncharged atom of phosphorus has an atomic number of 15. How many protons? How many electrons?
protons = 15 electrons = 15
the atomic number of oxygen, 8, indicates that there are 8
protons in the nucleus of an oxygen atom
what is the order that the orbitals are filled in
s, p, d, f
acids react with bases to produce what?
salt and water
the empirical formula for a compound shows the symbols of the elements with subscripts indicating the
smallest whole-number ratio of the atoms
what is the scientific name for NaBr?
sodium bromide (ionic)
what are properties of acids?
sour, pH of >7, turn indicators pink/red
what can you do to increase the rate of dissolving of a solid?
stir, heat, crush
the spin quantum number of an electron can be though of as describing
the direction of electron spin
If the energy of a collision is less than the activation energy...
the molecules bounce apart without reacting
an atom is electrically neutral because
the numbers of protons and electrons are equal
if you heat up a closed container of gas, what happens to the pressure?
the pressure increases (gay-lussacs)
what happens to the volume of a balloon if the temperature increases and the pressure remains unchanged?
the volume increases/expands (charles law)
how many electrons can occupy the s orbital at each energy level
two, if they have opposite spins
Mendeleev predicted that the spaces in his periodic table represented
undiscovered elements
what kind of solvent is water?
universal, polar
What determines how an atom is going to react with other atoms?
valence electrons
the electrons available to be lost, gained, or shared, when atoms form compounds are called
valence electrons
what is the oxidation number of Ca in Calcium Chloride?
+2
Charle's Law
-The Kelvin temperature of a gas is directly related to the volume of the gas, -P and n are constant, and -as the temperature of a gas increases, the molecules move faster and its volume increases to maintain constant P. v1/t1 = v2/t2 (P and N are CONSTANT)
Solute
-are spread uniformly throughout the solvent. -are not visible, but can give a color to the solution. -are usually present in a smaller amount than the solvent.
Oxidation-Reduction reaction
-electrons are transferred from one substance to another. -if one substance loses electrons, another substance must gain electrons -energy is provided to us from food -electrical energy is provided in batteries -iron rusts
Water
-is the most common solvent in nature. -is a polar molecule. -forms hydrogen bonds between the partially positive hydrogen atom in one molecule and the partially negatively charged oxygen atom in a different water molecule.
Dalton's Law
-states that the total pressure of a gas mixture is the sum of the partial pressures of the gases in the mixture. P(total)= P1+P2+P3 -indicates that pressure depends on the total number of gas particles.
Gay-Lussac's Law
-the pressure exerted by a gas is directly related to the Kelvin temperature. -V and n are constant. -an increase in temperature increases the pressure of a gas. P1/T1 = P2/T2
Boyle's Law
-the pressure of a gas is inversely related to its volume when temperature (T) and amount of gas (n) are constant. -if the pressure (P) increases, then the volume (V) decreases.
a nonpolar covalent bond is most likely to form between two elements that have a difference in electronegativity values of
0.1
what is the standard temp?
0°C
Lithium has an atomic number of 3. How many electrons are in its highest occupied energy level?
1
the number of valence electrons in group 1 elements is
1
Name 3 ways an atom can become stable
1) lose an electron 2) gain an electron 3) share an electron
The elements whose electron configurations end with s2 p5 in the highest occupied energy level belong to Group
17
Chlorine has atomic number 17 and mass number 35 it has
17 protons, 17 electrons, and 18 neutrons
phosphorus-33 (atomic number 15) contains
18 neutrons
what is the concentration of OH- in pure water?
1E-7
what is the standard pressure?
1atm or 760mmMg
How many electrons are in each energy level of Hydrogen? (electron configuration)
1e
what is the electron configuration for nitrogen, atomic number 7
1s2 2s2 2p3
the electron notation for aluminum (atomic number 13) is
1s2 2s2 2p6 3s2 3p1
How many electrons does the Helium atom have?
2
the spin quantum number indicates that the number of possible spin states for an electron in an orbital is
2
The atomic number of calcium is 20. How many electrons do you expect it to have?
20
an aluminum isotope consists of 13 protons, 13 electrons, and 14 neutrons, its mass number is
27
How many electrons are in each energy level of Boron? (electron configuration)
2e, 3e
How many electrons are in each energy level of Sulfur? (electron configuration)
2e, 8e, 6e
The electron configuration of aluminum, atomic number 13, is [Ne] 3s2 3p1. Aluminum is in Period
3
how many electrons are needed to completely fill the fourth energy level
32
How many valence electrons does Carbon have?
4
What is the percentage composition of CuCl2
47.27% Cu, 52.73% Cl
How many electrons are in the highest occupied energy level of a nitrogen atom?
5
The percentage composition of sulfur in SO2 is about 50%. What is the percentage of oxygen in this compound
50%
How many electrons does Carbon have?
6
How many neutrons does Carbon have?
6
How many protons does Carbon have?
6
What is the atomic number of Carbon?
6
the number of atoms in 1 mol of carbon is
6.02 E23
Avogadro's number
6.02 E23 atoms of an element
bromine, atomic number 35, belongs to group 17. How many electrons does bromine have in its outermost energy level.
7
the number of valence electrons in group 17 elements is
7
in drawing a lewis structure, each nonmetal atom except hydrogen should be surrounded by
8 electrons
Combustion reactions
A carbon-containing compound that is the fuel burns in oxygen from the air to produce carbon dioxide (CO2), water (H2O), and energy in the form of heat or a flame.
Solvent
A liquid substance capable of dissolving other substances
Nonelectrolytes
A molecular compound that does not ionize in water, preventing the solution from conducting electricity.
Redux
Another name for an oxidation-reduction reaction
which element has the following electron configuration [Ar] 4s2 3d10 4p5?
Bromine
a compound's empirical formula is C2H5. If the formula mass is 58 amu what is the molecular formula
C4H10
what is the formula for carbon tetrachloride?
CCl4 (covalent)
what is the formula for the compound formed by calcium ions and chloride ions
CaCl2
Conditions required for a chemical reaction to occur
Collision, orientation, and energy
Gas
Consists of small particles that move randomly with high velocities. -have essentially no attractive (or repulsive) forces toward each other. -have a very small volume compared to the volume of the containers they occupy. -are in constant motion. -have kinetic energies that increase with an increase in temperature.
Unsaturated solutions
Contain less than the maximum amount of solute present
Supersaturated solutions
Contain over the maximum amount of solute present in this condition. A supersaturated solution may provide for an unbalanced equation that leaves the formula incorrect. Be careful to balance the equation to account for the excess of the product. The rate at which the solute dissolves equals the rate at which the solute forms.
Saturated solutions
Contain the maximum amount of solute present
which elements orbital is shown
F
Reduction characteristics
Gaining electrons Loss of oxygen Gain of hydrogen DECREASE in the # of Carbon Oxygen bonds
a compound contains 64 g of O and 8g of H. What is the empirical formula for this compound
H2O
what is the formula for hydrofluoric acid?
HF
Limiting reactants
In a chemical reaction is the substance that is used up first and limits the amount of product that can form.
what is the empirical formula for a compound that is 31.9% potassium, 28.9% chlorine, and 39.2% oxygen
KClO3
Oxidation characteristics
Losing electrons Addition of oxygen Loss of hydrogen INCREASE in the # of Carbon Oxygen bonds
