List of Standard States of Elements and Ions

PDF LINK: Standard_States_of_Elements_&_Key_Ions

Standard States of Elements

The standard states of elements are the forms that they adopt at a temperature of 25°C and pressure of 1 atmosphere (1 atm).
These forms of the elements are the reactants in the formation equations of multi- element substances.

The heat of formation (∆H°f) of an element in its standard state is zero.

Below is the list of the elements whose standard states you need to know for this course. Please note that some elements have multiple possible forms at the standard state such as carbon, which can be either graphite or diamond. However only one of these forms is the true standard state; in those cases the proper state will be listed next to the formula for the element.

Gases

• Hydrogen            H2(g)
• Nitrogen              N2(g)
• Oxygen                O2(g)
• Fluorine               F2(g)
• Chlorine               Cl2(g)

Liquids

• Bromine               Br(l)
• Mercury               Hg(l)

Solids

There are two distinct classes of elemental solids. Molecular solids, unlike other elemental solids, have specific molecular structures (arrangements of bonded atoms) that are packed close to each other (held by van der Waals forces) to form the solid. The atoms of a molecular solid are only bonded to the other atoms in their specific molecule, unlike the elements in the other elemental solids, which are bound to all their nearest neighboring elements.

Molecular Solids

Phosphorus          P4 – white

Sulfur                   S8(s) – rhombic crystalI2(s)

Iodine                   I2(s)

Solids (Non-Metal)

Silicon                  Si(s)

Carbon                 C(s) – graphite

Solids (Metal)

Lithium                Li(s)

Magnesium          Mg(s)

Sodium                Na(s)

Calcium               Ca(s)

Potassium             K(s)

Aluminum            Al(s)

Iron                      Fe(s)

Nickel                  Ni(s)

Copper                Cu(s)

Zinc                     Zn(s)

Silver                   Ag(s)

Gold                    Au(s)

Common Ionic Species in Aqueous Solution

Below is the list of common aqueous ions that you are expected to know for this course. You need to know the name, formula, and charge of each ion as the names and formulas will be used interchangeably in homework and exam questions.

Cations (positively charged ions)

Lithium ion

Sodium ion

Potassium ion

Silver ion

Copper(I) ion

Hydronium ion

Ammonium ion

Zinc ion

Cadmium ion

Magnesium ion

Calcium ion

Barium ion

Mercury(II) ion

Nickel(II) ion

Copper(II) ion

Lead(II) ion

Aluminum ion

Chromium(II) ion

Chromium(III) ion

Iron(II) ion

Iron(III) ion

Cobalt(II) ion

Cobalt(III) ion

Tin(II) ion

Tin(IV) ion

Manganese ion

Manganese(IV) ion

 

Anions (negatively charged ions)

Fluoride ion
Bromide ion
Iodide ion
Oxide 
Hydroxide
Nitride
Nitrite
Nitrate
Cyanide
Chloride ion
Hypochlorite
Chlorite
Chlorate
Perchlorate
Sulfide 
Sulfite 
Sulfate 
Hydrogen sulfate
Phosphate
Hydrogen phosphate 
Dihydrogen phosphate
Carbonate 
Hydrogen carbonate
Acetate 
Permanganate 
Molybdate

Standard_States_of_Elements_&_Key_Ions

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The Final is Saturday, December 15th at 7:30 pm. Here is the link to the Exam Room Assignments: Final Room Assignment  Make sure you arrive early and you bring the following:

  1. Non-graphing, non-programmable calculator
  2. Pencil
  3. RedID card and/or Driver’s License