-The lattice energy is a measure of the strength of an ionic bond. -Lattice energy is the energy released in the formation of an ionic compound.
-Compared with energies of neutrons,crystal lattice has a lower potential evergy.
-If the lattice energy of compound A is greater than that of compound B,the bonds in compound A are stronger then the bonds in B.
-When an electron is added to an atom, energy is usually released.
-When ions are formed, energy can be released or absorbed.
-Ionic compounds have high boiling points,are brittle but hard substances, and the molten compounds conduct electricity. Molecular compounds have lower boiling and melting points.
-Because particals in ionic cpmpounds are more strongly attached then in molecular compounds,the melting points of ionic compounds are higher then molecular compounds.
-Ionic compounds are brittle because the strong attractive forces hold the layers in relatively fixed positions.
-The symbol (HCO3)1- represents a polyatomic, which represents a bicarbonate.
-A comparison of calcium sulfate and calcium sulfite shows that both have a monatomic cation and a polyatomic anion.
-The oxidation number of fluorine is 1-.
-The oxidation number of oxygen in most compounds is 2-.
-The oxidation number of an uncombined element is zero.
-In a compound, the algebraic sum of the oxidation number of all atoms equals zero.
-In a polyatomic ion, the algebraic sum of the oxidation number of all atoms is equal to the charge of the ion.
-The oxidation number of hydrogen in most compounds is 1+.
-The oxidation number of oxygen in H2O2 is 1-.
-The oxidation number of carbon in CI4 is 4+.
-The oxidation number of hydrogen in KH is 1-. -The oxidation number of hydrogen in H2O is 1+.
-The formula Na2CO3 . 10H2O shows that there are 10 units of water present for every unit of Na2CO3.