CHEM 101: Final Exam Equations/Conversions

What are the base quantities and units of the SI system?

Time (t), second (s)

Mass (m), kilogram (kg)

Amount of substance (n), mole (mol)

Luminous intensity (lv), candela (cd)

Temperature (T), kelvin (K)

Electric Current (I), ampere (A)

Length (l), meter (m)

Converting Between Kelvin and Celsius

Temperature in Kelvin= 273.15 + Temperature in Celsius

Converting Between Fahrenheit and Celsius

Temperature in Fahrenheit= 9/5 * Temperature in Celsius + 32

What is an Angstrom?

10^-10 m

What are the Common Unit Prefixes?

femto (f), 10^-15

pico (p), 10^-12

nano (n), 10^-9

micro (µ), 10^-6

milli (m), 10^-3

centi (c), 10^-2

deci (d), 10^-1

deka (da), 10^1

hecto (h), 10^2

kilo (k), 10^3

mega (M), 10^6

giga (G), 10^9

tera (T), 10^12

Density

Density= mass/volume

Centimeters Cubed to Milliliters

1 cm³= 1 mL

Inches to Centimeters

1 in= 2.54 cm

Atomic Mass Units to Grams

1 amu= 1.6605 × 10^-24

Number of Neutrons

Number of Neutrons= Mass Number- Atomic Number

Average Atomic Mass

Average Mass= The Sum of (Fractional Abundance * Isotopic Mass)

Charge of an Ion

Charge of Ion= Number of protons - Number of Electrons

Diatomic Molecules

H, N, O, F, Cl, Br, I

Ammonium

NH4^+

Peroxide

O2^2-

Hydroxide

OH^-

Acetate

C2H3O2^-

Cyanide

CN^-

Carbonate

CO3^2-

Bicarbonate

HCO3^-

Nitrate

NO3^-

Nitrite

NO2^-

Sulfate

SO4^2-

Hydrogen Sulfate

HSO4^-

Sulfite

SO3^2-

Hydronium

H3O^+

Hydrogen Sulfite

HSO3^-

Phosphate

PO4^3-

Hydrogen Phosphate

HPO4^2-

Dihydrogen Phosphate

H2PO4^2-

Perchlorate

ClO4^-

Chlorate

ClO3^-

Chlorite

ClO2^-

Hypochlorite

ClO^-

Chromate

CrO4^2-

Dichromate

Cr2O7^2-

Permanganate

MnO4^-

Oxalate

C2O4^2-

Thiosulfate

S2O3^2-

Azide

N3^-

Nomenclature Prefixes

1, mono

2, di

3, tri

4, tetra

5, penta

6, hexa

7, hepta

8, octa

9, nona

10, deca

Formula Mass

Formula Mass= # of element (molar mass) + # of element (molar mass)

Avogadro’s Number

6.022 × 10^23

Speed of a Wave

c= yv

Speed of Light

c= 2.998 × 10^8 m/s

The Energy and Frequency of a Photon

E= hv

Planck’s Constant

h= 6.626 × 10^-34 J*s

Energy of Photon

E= hc/y

Frequency

v

Wavelength

y

Energy Change of Energy Level Transitions

Change in Energy= E final - E initial = -2.18 × 10^-18 J (1/nf² - 1/ ni²)

de Brogile Equation

y= h/mv

Effective Nuclear Charge

Zeff= Atomic Number - Number of Core Electrons

Ionization Energy

X(g) → X^+ (g) + e^-

Electron Affinity

X(g) + e^- → X^- (g)

Formal Charge

Formal Charge= # of valence - # of lone pairs - ½ bonding electrons

Bond Order

Bond Order= # of bonds are central atom / # of bonding sites

Names, Angles, Bonds, Electrons, and Lone Pair Structures

Hybridization Numbers

Linear, 2sp

Trigonal Planar, 3sp²

Tetrahedral, 4sp³

Trigonal Bipyramidal, 5sp³d

Octahedral, 6sp³d²

Percent Composition

Percent Composition= (# of atoms * mass of element)/mass of compound * 100

Concentration

c= amount of solute/ solvent of solution

Molarity

M= mol of solute/ liters of solution

Stock and Dilution Concentration

M1L1=M2L2

Mass Percentage

Mass Percentage= mass of solute/mass of solution *100

Parts per Million

ppm= mass of solute/mass of solution * 10^9

Parts per Billion

ppb= mass of solute/mass of solution * 10^9

Volume Percent

Volume Percent= volume of solute/volume of solution * 100

Mass Volume Percent

Mass Volume Percent= mass of solute/volume of solution * 100

What are the strong acids?

HBr, hydrobromic acid

HCl, hydrochloric acid

HI, hydroiodic acid

HNO3, nitric acid

HClO4, perchloric acid

H2SO4, sulfuric acid

Percent Yield

Percent Yield= actual yield/theoretical yield * 100

Enthalpy

Change in H= E +(P * Change in V)

Bond Enthalpy/Energy

Change in H degree= Sum of BE bonds broken - Sum of BE bonds formed

Hess’s Law and Enthalpies of Formation

Atmospheric Pressure and Pascals

1 atm= 101325 Pa

Atmospheric Pressure and mmHg

1 atm= 760 mmHg

mmHg and Torr

1 mmHg= 1 torr

A Mol of Gas at Ideal Temperature

22.4 L

Calorie to calorie

1 Cal= 1 Kcal

calorie to Joules

1 cal= 4.184 J

The Specific Heat of Water

4.184

R in Gas Equations

r= 0.08206 atm

r= 8.314 J

Standard Temperature and Pressure

1 atm, and O degrees Celsius (273.15 K)

Dalton’s Law

Ptotal= the sum of (Pa + Pb…)

Exothermic Values

Negative work, heat, and internal energy.

Endothermic Values

Positive work, heat, and internal energy.

Kinetic Energy and Temperature

KEavg is proportional to temperature in Kelvin.

Manometer Equations

Pressure and Temperature

P1/T1=P2/T2

Volume and Temperature

V1/T1=V2/T2

Pressure and Volume

P1V1=P2V2

Volume and Moles

V1/n1=V2/n2

Combined Gas Law

P1V1/T1=P2V2/T2

Ideal Gas Law

PV=nRT

Density in Gas

d=PM/RT

Molar Mass in Gas

M=dRT/P

Atmospheric Pressure

Patmosphere= Pgas + Pwater

Partial Pressure

Pa= Xa * Ptotal

Mole Fraction

Xa= na/ ntotal

Root Mean Square Velocity

Average Kinetic Energy

KEavg= 1/2m(Urms)²

KEavg= 3/2RT