CHEM EXAM 2

HCL

hydrochloric acid, strong acid

is hydrochloric acid strong or weak?

strong

HCL products when reacting with water

Cl- + H3O+

HBr

hydrobromic acid, strong acid

Is hydrobromic acid strong or weak?

strong

HBr products when reacting with water

Br- + H3O+

HI

hydroiodic acid, strong acid

is hydroiodic acid strong or weak

strong

HI products when reacting with water

I- + H3O+

HNO3

nitric acid (strong acid)

is nitric acid strong or weak

strong

HNO3 products when reacting with water

NO3- + H3O+

H2SO4

sulfuric acid, strong acid

is sulfuric acid strong or weak

strong

H2SO4 products when reacting with water

HSO4- + H3O+

HClO3

chloric acid, strong acid

is chloric acid strong or weak

strong

HClO3 products when reacting with water

ClO3- + H3O+

HClO4

perchloric acid, strong acid

is perchloric acid strong or weak

strong

HClO4 products when reacting with water

ClO4- + H3O+

What do strong acids do in water?

They ionise completely - all acid particles dissociate to release positive hydrogen ions

are strong acids ionic or molecular

molecular

Are weak acids ionic or molecular

molecular

are strong bases ionic or molecular

ionic

are weak bases ionic or molecular

molecular

how do molecular compounds dissociate in water

dipole-dipole rxns, most don't dissociate

Dipole-Dipole reaction

molecules with permanent dipoles attract each other electrostatically; the positive end of one molecule attracts the negative end of another molecule, and so on, leading to an alignment of the molecules

molarity

the number of moles of solute per liter of solution

molarity equation

moles of solute/liters of solution

molecular compound

a chemical compound whose simplest units are molecules,

If water is added to an existing solution, what happens to volume and mols of solute?

mols are unchanged but volume increases

soluble compounds

able to dissolve in water

how do polyatomic ions interact?

they do not dissociate

Solvation/Hydration

dissolved particles are surrounded by water molecules; thepositive end of H2O points towards the anions and the negative end of H2Opoints towards the cations

what attractive force between ions w/in ionic compounds and ions w/ water causes a solution to dissolve

when force btw ions and water > ions in ionic compound

acids

compounds that form hydrogen ions when dissolved in water, H+ ionizes in aqueous solution

complete ionization

the condition when all donor atoms are positively charged by giving up their donor electrons and all acceptor atoms are negatively charged by accepting electrons. WEAK ATTRACTION

partial ionization

weak acid seperate only some of the ions in aqueous solution. STRON ATTRACTION

strong electrolytes

soluble ionic compounds, strong acids, strong bases. Strong conductor, many ions present, 100% ions in solution

weak electrolytes

weak acids and weak bases, weak conductor,

non electrolytes

molecular compounds, no ions present, not a conductor

precipitation rxn

(aq) + (aq) --> (s) + (aq)

acid-base rxn

A special type of double replacement rxn in which water and a salt are produced (HY + XOH --> H2O + XY)

molecular equation

a reaction equation that shows the complete chemical formulas of all reactants and products

total ionic equation

an equation for an aqueous reaction that shows all the strong electrolytes dissociated into ions. Weak and non electrolytes are intact undissociated compounds

net ionic equation

an equation for a reaction in solution showing only those particles that are directly involved in the chemical change, eliminates spectator ions

spectator ions

Ions that do not take part in a chemical reaction and are found in solution both before and after the reaction

precipitation reaction

The formation of a solid from a solution during a chemical reaction. Precipitates are often formed when two aqueous solutions are mixed together. More than one solid product is possible. Forms with net removal of ions

homogenous and heterogenous solutions in ions

2 homogenous ionic mixtures (g) form a heterogenous mixture (s or l)

conversion factor for mols to entities (atoms, molecules, ions..)

Avogadro's #

conversion factor for mols to volume

molarity of solution (# mols/volume in L)

6 strong acids:

HCl, HBr, HI, HNO3, H2SO4, HClO4

strong bases

group 1 hydroxides

Ca(OH)2

Sr(OH)2

Ba(OH)2

Strong acid/electrolyte + strong base/electrolyte equation

molec: all products and reactants as if not dissociated

total ionic: all strong electrolytes dissociate into ions (strong bases, strong acids, soluble ionic compounds)

weak acid/electrolyte + strong base/electrolyte

Weak acids don't dissociate!

titration

A solution of known concentration is used to determine the concentration of another solution.

titrant

the standard solution added to the sample in a titration: KNOWN CONC

buret

dispensing and transferring known volumes of fluids

Indicator

a compound that can reversibly change color depending on conditions such as pH

equivalence point

the point at which the two solutions used in a titration are present in chemically equivalent amounts

end point

the point in a titration at which an indicator changes color

Gas

A state of matter with no definite shape or volume

- particles far apart

- particles fill shape of container

- compressible

liquid

A state of matter that has no definite shape but has a definite volume.

- particles close together

- not compressible

solid

A form of matter that has a definite shape and volume

- particles tightly packed

- not compressible

particle mobility of gas

- high mobility and velocity

- constant motion

particle mobility of liquid

less freedom of motion than gas

particle mobility of solid

immobile

attractive forces between gas particles

little to no attraction

attractive forces between liquid particles

moderate attraction

attractive forces between solid particles

strong attraction

Kinetic Molecular Theory of Gases

a model used to explain the behavior of gases

- tiny with large spaces in btwn

- constant random straight line motion until collision, which is elastic

- assumed to exert no force on each other, no attraction or repulsion

- avg kinetic energy of a collection of gas particles is directly proportional to temp of gas in K

Kinetic molecular theory equation and explanation

Kinetic energy= 1/2(mass)(velocity)^2

molecules of different gases at the sametemperature always have the same average kinetic energy. Average kinetic energydepends only on the temperature.

pressure=

force/area

Atmospheric pressure arises from

the force exerted by atmospheric gases on the earth's surface

what natural force can decrease atmospheric pressure

increasing of altitude

common value of pascal (Pa)

1.01325 (10^5)

common value of kilopascal (kPa)

101.325

common value of atmosphere (atm)

1

common value of millimeters of mercury (mmHg)

760

common values of torr

760

common unit of lbs per square inch (lb/in^2)(psi)

14.7

common unit of bar

1.01325

1 atm=

760 mmHg= 760 torr

Gas Laws

the laws that state the mathematical relationships between the volume, temperature, pressure, and quantity of a gas

ideal gas

a hypothetical gas that perfectly fits all the assumptions of the kinetic-molecular theory, does not exist but most simple gases behave almost ideal @ normal temp and pressure

Boyle's Law

A principle that describes the relationship between the pressure and volume of a gas at constant temperature

P1V1=P2V2

Boyle's Law Equation

P1V1=P2V2

Charles's Law

the law that states that for a fixed amount of gas at a constant pressure, the volume of the gas increases as the temperature of the gas increases and the volume of the gas decreases as the temperature of the gas decreases. V AND T DIRECTLY PROPOERTIONAL

Charles's Law Equation

V1/T1 = V2/T2

Absolute zero

The coldest temperature, 0 Kelvin / -273.15 C, that can be reached. It is the hypothetical temperature at which all molecular motion stops.

Amonton's Law

if the volume of a gas is held constant, increasing the temperature of the gas increases its pressure. P AND T ARE DIRECTLY PROPORTIONAL

Amonton's Law equation

P1/T1=P2/T2

Avogadro's Law

equal volumes of gases at the same temperature and pressure contain equal numbers of molecules

Avogadro's Law equation

V1/n1=V2/n2

n= # mols

standard temp in C

0

STP

standard temperature and pressure

Ideal Gas Law

the relationship PV=nRT, which describes the behavior of an ideal gas

direct proportionality

one value increases as another increases

indirect proportionality

one factor goes up, the other goes down