what is a period on the periodic table?

what is the difference between periods?

a row

they have different energy levels 

which electrons are highest energy and which are in the outermost energy shell?

4s or 3d?

which would be the valence electrons?

4s is the outer most of the two

3d electrons have the highest energy

the 4s are the valence electrons

d = period -1

f = period - 2

there are d levels of 3,4,5, and 6

and f levels of 4 and 5

because they s orbitals are farther out than the d's but they are filled first

chromium and copper are 2 exceptions

each period is a shell and within each shell you have different s,p,d,f orbitals or subshells.

How many valence electrons does Sn have?

how many electrons do atoms want to have in their outermost shell? why?

not orbital but shell

8

experiments have proven we're not sure why

atoms are not very reactive when they have 8 in their outermost shell

alkali metals, except hydrogen, they are highly reactive especially with halogens

they are not often found in elemental form because they are so reactive, same with halogens

What is the best conductor?

What makes a good conductor?

Silver Ag is the best

having available electrons makes a good conductor

flow of electrons is electricity

halogens, they are very reactive and want to gain 1 electron

halogens lamps come from this

what is ionization energy?

how does it trend?

the energy it takes to remove an electron, or the energy to make something into a cation

low to high is up and to the right

so generally Cs is really low and and He is really high 

what is electronegativity?

what is the trend on the periodic table?

how much an element hogs electrons in a covalent bond

up and to the right

Cs low, F highest (noble gases don't form covalent bonds)

same trend as ionization energy

what is metallic nature in chemistry?

how does it trend?

a willingness to give away electrons

down and to the left it increases

Cs has has high metallic nature F has low

increases down and to the left, because when you move to the right, it increases your protons so it pulls in the electrons stronger

in a period, the more protons you have, the small the atom

bonds that metals make,

they give up their electrons and form a sea of electrons they all share, the electrons can be moved around. This is why metals are maleable and good conductors

figured out through experience or experiment

ratio of elements in a molecule

atomic mass units

the mass of the atom or molecule, it the weighted average of all the molecules or atoms in nature. C amu is 12.0107 so there is a lot more C with a mass of 12 then 14

amu is the mass of the neutrons + mass of protons

it avogadros number = 6.02 * 10²³

1 mole of C twelve = 12 grams of C twelve

or 6.02 * 10²³ atoms of C twelve = 12 grams of C twelve

it's the conversion from grams to amu's

1 gram = 1 mole of amu's

how do you solve for mass composition or get empirical formula from mass composition?

9% Mg

91% I

assume there is 100 grams

9 grams of Mg

91 grams of I

MgI₂

force/area

PV = nRT

assuming the particles aren't attacted to each other and the particle volumes are insignificant

What is temperature?

what is heat?

temperature is the average kinetic energy of particles

heat is the transfer of energy from one substance to another measured in 1 calorie = 4.184 Joules

potential energy is in bonds

mass is the amount of matter in an object

weight is the amount of force pulling an object to the center of the earth

(1.5 * 10³g) + (2.3 * 10²g) =?

(9.25*10^-2 m) * (1.37*10^-5 m) =?

have to have same power for add and subtract = (1.73 * 10³ g)

multiply the coefficients and add the exponents = (1.27*10^-6 m²)

2 because you can write it as 2.3 *10^-3

how many sig figs?

0.000230340

6

zeroes inbetween non-zeroe numbers and after are significant.

how many sig figs?

50,500?

3

if it doesn't contain a decimal, the zeroes after nonzero digits aren't normally considered significant

how do you determine sig figs to report in you answer?

1) add/subtract

2) multiply/divide

1) fewest number of decimals

2) fewest # of sig figs in calculations (exact or counted #'s used in conversions don't count)

what is the change from a gas to a solid called?

an instrument to measure pressure of a gas ina container

a container connected to a U-shaped piece of glass with mercury in the bottom of the U

what is Boyle's law?

suppose you have 5.00 liters of a gas at 1.00 atm pressure and then to decrease the volume to 2.00 liters. What's the new pressure?

Pressure and Volume have and inverse relationship, if volume goes up pressure goes down.

P₁V₁ = P₂V₂

2.5 atm

the relationship of Volume and Temperature is directly related

you have to use Kelvin

V₁/T₁ = V₂/T₂  when pressure is held constant and temp in K

The relationship between the temperature and pressure of a gas is directly related. Increase temp and you increase pressure. (assuming volume and amount is constant)

P₁/T₁ = P₂/T₂

volume and moles or amount of particles are directly proportional

V₁/n₁ = V₂/n₂ 

you need it when you do not have ideal gases

(P+(an²/V²))*(V-nb) = nRT

in a mixture of gases, the total pressure is the sum of the partial pressures of each individual gas.

P_total = P_a + P_b + P_c

how gases diffuse and effuse(Helium escaping through a rubber balloon over time)

v_1/v₂ = sqrt(M₂/M₁)

M = molecular or atomic weights

v = velocity of diffusion

what is vapor pressure?

why would something want to evaporate?

the pressure at which the vapor and liquid pressures are at equillibrium

high kinetic energy(high temp)

low intermolecular forces (methane,carbon bonds-unlike water has hydrogen bonding)

light molecules

(these will have a high vapor pressure) high volitility

the heat required to change from a solid to liquid state. for a period of heat and time, a solid doesn't increase in temp with added heat. The heat is used to break the bonds. So you can have 0 degree ice and 0 degree water

same as heat of melting

the additional heat to turn a liquid to a gas. at 100 degrees it takes additional heat to break the bonds and changes phases. You can have 100 dregree water and vapor

same as heat of condensation

Inorganic Compounds

Ammonium (NH 4 + ),potassium (K + ), sodium (Na + ) : All ammonium, potassium and sodium salts are soluble. Exceptions: some transition metal compounds.

Bromides (Br–), chlorides (Cl–) and iodides (I–): Most bromides are soluble. Exceptions: salts containing silver, lead, and mercury.

Acetates (C2H3O2–): All acetates are soluble. Exception: silver acetate is only moderately soluble.

Nitrates (NO3–): All nitrates are soluble.

Sulfates (SO42–): All sulfates are soluble except barium and lead. Silver, mercury(I), and calcium sulfates are slightly soluble. Hydrogen sulfates (HSO4–) (the bisulfates) are more soluble than the other sulfates.

Generally Insoluble Inorganic Compounds

Carbonates (CO 3 2– ), chromates (CrO 4 2– ), phosphates (PO 4 3– ), silicates (SiO 4 2– ): All carbonates, chromates, phosphates and silicates are insoluble. Exceptions: those of ammonium, potassium and sodium. An exception to the exceptions is MgCrO 4 , which is soluble.

Hydroxides (OH–): All hydroxides (except ammonium, lithium, sodium, potassium, cesium, rubidium) are insoluble. Ba(OH)2, Ca(OH)2 and Sr(OH)2 are slightly soluble.

Silver (Ag+): All silver salts are insoluble. Exceptions: AgNO3 and AgClO4. AgC2H3O2 and Ag2SO4 are moderately soluble.

Sulfides (S2–): All sulfides (except sodium, potassium, ammonium, magnesium, calcium and barium) are insoluble.

Aluminum sulfides and chromium sulfides are hydrolyzed and precipitate as hydroxides.

steps to balance redox

Fe + Cl2 yields Fe3+ + Cl-

1. write half reactions (LEO and GER)
2. balance atoms other than O and H
3. balance O's by adding water
4. balance H's by adding H+
5. balance charge by adding electrons
6. make number of electrons equal and add half reactions
7. if basic, add OH atoms to balance H+

define colligative properties

In chemistry, colligative properties are properties of solutions that depend upon the ratio of the number of solute particles to the number of solvent molecules in a solution, and not on the type of chemical species present.^[1] This number ratio can be related to the various units for concentration of solutions. Here we shall only consider those properties which result because of the dissolution of nonvolatile solute in a volatile liquid solvent.^[2] They are independent of the nature of the solute particles, and are due essentially to the dilution of the solvent by the solute. The word colligative is derived from the Latin colligatus meaning bound together.^[3]

Colligative properties include:

1. Relative lowering ofvapor pressure
2. Elevation of boiling point
3. Depression of freezing point
4. Osmotic pressure.

not density