How do we form salts in chemistry?

Ionic bond

The ionic bond leads to the formation of Salt. The best-known salt is sodium chloride, the table salt that is essential for us. But there are many more salts! You will be through Salt formulas which refer to the structure of the crystal lattice of salts.


Give with this bond Metal atoms give their outer electrons to non-metal atoms from. By donating electrons, they form Metal cations (positively charged). When a metal releases its outer electrons, the shell underneath becomes the full outer shell.
When the non-metal atoms take up electrons, they form Non-metal anions (negatively charged). The attraction between the now positively charged cations and the negatively charged anions are formed Crystal lattice (Salts). A very well known salt is sodium chloride (NaCl), which Table salt.

Salts and salt forms

The attraction between cations and anions creates regular lattices, which are called Crystal lattice, Ion lattice or Salts are designated. Salts are through Salt formulas which indicate the ion ratio in the crystal lattice. One speaks therefore of ratio formulas. Salts are outwardly uncharged, which is why they are always in a crystal lattice as many positive as negative Charges are present. Since sodium ions are simply positively charged and chloride ions are simply negatively charged, the ion lattice of sodium chloride (NaCl) consists of as many cations as anions. In order to be able to set up the salt formulas, one must know the charges of the ions.

Charge of cations

Metals release their outer electrons in order to achieve a full outer shell. The positive charge of the ion corresponds to that Number of electrons given off: Magnesium from the second Main group has two outer electrons and gives off both. The protons in the nucleus are in the majority - the charge of the ion is thus 2+ (one writes: Mg2+).

Charge of anions

Non-metals accept electrons to achieve a full outer shell. The negative charge of the ion corresponds to that Number of electrons picked up: Oxygen from the 6th main group has 6 outer electrons and therefore takes 2 more. The charge of the ions is therefore 2- (O2-). One can also calculate the charge of the anions (in most cases): Main group number minus 8.

Establishing salt formulas and salt names

  • The cation (metal) always comes before the anion (non-metal): NaCl (sodium chloride).
  • Metal cations bear the name of the element (sodium)
  • If there is only one type of non-metals in the salt, the name of the anion ends with "id“: Sodium chloride.
  • If the anion consists of several types of atoms (composite anion), it receives one own name: CuSO4 (Copper sulfate)
  • Must always be in the empirical formula as many positive as negative charges occur (salts are externally uncharged).
  • It has to be simplest ion ratio given: MgCl2 (Magnesium chloride), not: Mg2Cl4
Some anions have a short name derived from their Latin name (oxide ion).
F.-1-fluorideSodium fluoride (NaF)
Cl-1-chlorideMagnesium chloride (MgCl2)
Br-1-bromidePotassium bromide (KBr)
I.-1-IodideCalcium iodide (CaI2)
O-2-oxideLithium oxide (Li2O)
S.-2-sulfideRubidium sulfide (Rb2S)
N-3-NitrideAluminum nitride (AlN)
P.-3-PhosphideCalcium phosphide (approx3N2)

Compound anions

NO3-1-Nitrate ionPotassium Nitrate (KNO3)
NO2-1-Nitride ionSodium nitride (NaNO2)
CO32-2-Carbonate ionMagnesium carbonate (MgCO3)
SO42-2-Sulfate ionCalcium sulfate (CaSO4)

With this knowledge, can you now assemble salts yourself?
Try it!