(NOT MINE) TTU CHEM 1307 Exam II

Empirical Formula

Lowest whole number of moles
ex: HO

Molecular formula

actual number of atoms each element in a molecule
ex: H2O2

Structural formula

shows relative placement and connections of atoms
ex: H-O-O-H

Steps to find empirical formula

1. find mass of each element
2. convert mass to moles
3. write preliminary formula
4. convert moles to whole numbers by dividing each subscript by the smallest number

Molecular formula structure

whole number multiple= molar mass/ empirical formula mass

Theoretical yield

amount of product calculated from the mole ratio in the balanced equation

Actual yield

amount of product actually obtained

Percent yield

actual yield expressed as a percentage: % yield= (actual yield/ theoretical yield)x100%

Mass of element equation

Mass compound x (mass of 1 mol of element/ mass of 1 mole of compound)

Solute

solution consists of smaller quantity of substance

Solvent

solution substance was dissolved in

Dissolution

occurs because attraction between each type of ion and several H2O molecules outweigh the attractions between the ion themselves

Molarity equation

mole of solute/ L of solution

Soluble compounds

All:
Group 1A element (Li+, Na+,K+, Rb+, Cs+, and Fr+)
ammonium ions (NH4+)
nitrates (NO3-)
acetates(CH3COO- or C2H3O2-)
perchlorates (ClO4-)
chlorides (Cl-)
bromides (Br-)
iodides (I-)
flourides (F-)
sulfate (SO4-)

Insoluble compounds

All:
metal hydroxides
carbonate (CO3 2-)
phosphates (PO4-)
sulfides (S2-)

Acids

substances that produce H+ ions when dissolved in H20

Base

substance that produces OH- ions when dissolved in H2O

Equivalent point

occurs when the amount of moles of H+ ions in the original volume of acid reacted with the same amount of OH- ions

End point

occurs when tiny excess of OH- ions change the indicator permanently to its basic color

Ionic compounds

transfer electrons

Covalent compounds

shift or share electrons

Oxidiation

the loss of electrons

Reduction

the gain of electron

Oxidizing agent

the species causing electrons to be loss

Reducaing agent

the species causing electrons to be gained

Pressure

the force exerted per unit of surface area
Pressure= Force/ area

Barometer

measures atmoshperic pressure

PHg directly proportional to

height

unit of measurement of P

mmHg

Manometer

measure of P in grams in experiment

SI unit of P

Pascal (Pa)

1 Pa=

1 N/m2

1 atm =

101.325 kPa or 1.01325 x 10^5 Pa

1 torr=

1 mmHg=1/760 KPa= 133.22 Pa

1 bar=

1 x 10^2 KPa= 1x 10^5 Pa

Relationship between Volume and Pressure

Boyles Law with J shaped tube

V=constant/P or PV= constant

P increase V decreases, P decreases V increases
law focuses on external pressure

Relationship between Volume and Temperature

Charles law with water bath

V= constant x T or V/T= constant

T increases V increases, T decreases V decreases

liner relationship between V and T
V and T are directly proportional

Relationship between Pressure and Temperature

Amontons Law

P= constant x T or P/T= constqant

T increase P increases, T decreases P decreases
Combining gas laws:
V= constant x T/P or PV/T = constant

Relationship between Volume and Amount

Avogadros Law

V= constant x n or V/n = constant

n increases V increases, n decreases, V decreases

STP ( Standard Temperature and Pressure)

0 degrees C= 273.15 K, 1 atm = 760 torr

Standard molar volume

22.4141 L or 22.4 L

Ideal Gas Law

PV= nRT

R= proportionally constant= universal gas constant P1V1 and P2V2= nRT

Ideal Gas Law and Density

d= (P x molar mass)/ RT

d=
- directly proportional to molar mass
- inversely proportional to temp
- directly proportional to P

Relationship between Volume and Amount

Avogadros Law

1 torr=

1 mmHg

1 Pa=

1 N/m2

unit of measurement of P

mmHg

PHg directly proportional to

height

Reduction

the gain of electron

Oxidiation

the loss of electrons

Ionic compounds

transfer electrons