chem final exam

1.all salts that contain __________or NH4 (ammonium ion) are soluble.

group 1a metals- Li,Na, K etc

2.all salts with__________ are soluble.

NO3(Nitrate ion),CH3COO, CIO4, or CIO3

3. most salts with cl, br or I are soluble except if the metal is

ag,pb, or hg2

4. most salts with so4 are soluble except

group 2a metals Mg2 ,Ca2 ,Ba2, etc or Ag, Pb, Hg2

the _____ _____ is a book keeping device used to assign charges to atoms if all compounds are ionic in nature.

oxidation number

1 all elements are assigned an oxidation number equal to

0

the oxidation number of group _________ metals in a compound is equal to the group number

1a,2a,3a

the oxidation number of group 4a metals in a compound is equal to

+2 or +4

the oxidation number of f in compounds is always equal to

-1

the oxidation number of o in compounds is usually equal to ________. some exceptions are H2O2, where 0=____ and KO2, where o=____.

-2,-1,-1/2

metal ion

the oxidation number of H in compounds is usually equal to +1, unless it is bound to a __________then it is -1.

the oxidation numbers but add up to _____ in a neutral compound.

zero

the oxidation numbers _______ to the charge of a polyatomic ion.

must add up

precipitation reaction

occurs when two solutions are mixed and a solid, or precipitate, is formed due to a chemical reaction.

neutralization reaction

a strong acid reacts with a strong base to form water and normally a soluble salt. in this reaction, heat is generated by the reaction, therefore the temperature of the solution increases.

oxidation-reduction reactions

involve the transfer of electrons from one substance to another.

displacement reactions

where one atom displaces another atom from a compound

combination reactions

where a compound is formed from two species.

decomposition reactions

where a compound breaks down into two or more substances.

combustion reaction

where a compound is burned (reacts with O2) to produce two or more substances.

a gas is composed of __________that are separated by ______ distances.

particles, large

gas molecules are constantly in random ______, moving in _______, colliding with perfectly elastic ______.

motion, straight paths, collisions

gas molecules do not exert ___________ on one another.

attractive or repulsive forces

the average kinetic energy of a gas molecules in a sample is______ to the ________ temperature.

proportional, absolute

solution

homogeneous mixture at the molecular level

solute

the part of the solution in the smaller amount that is said to be “dissolved“ in the solution.

solvent

the part of the solution in the greatest amount that dissolves the solute

Electrolyte solution

when a solute is placed in water, it dissolves or reacts to form ions.

strong electrolyte

completely dissolves in water to form 100% ions.

weak electrolyte

salts that only slightly dissolve and are considered not soluble.

non-electrolyte solution

solute dissolves in water but does not produce ions.

acid-base reactions

acid or base react with water forming ions (ionization)acid is any substance that when placed in water reacts to produce the h3o ion (hydronium)

HCI(hydrochloric acid), HNO3 (nitric acid), HCIo4(perchloric acid), H2SO4 (Sufic acid)

the four strong acids

base

any substance placed in water that reads or dissolves to produce OH ions (hydroxide)

specific acid-base

neutralization reaction occurs when an acid reacts with a base producing water and a salt (ionic compound).

solutions

combination of a solute + solvent

concentration of a solution

define the amount of solute present in a given amount of solution.

molarity

a concentration defined as the number of moles of solute dissolved making one liter of solution.

m=

moles of solute/ liter of solution

molar mass=

g substance/ 1 mol substance

(molar mass)(moles )=

grams

M x liters=

moles of solute

dilution

method that lowers the concentration of a solution by adding more solvent

moles solute concentrated=

moles of solute diluted