For your question many volumes are necessary ! Read first a general chemistry book.
There are no 'common' compounds of krypton.
Cinnabar (HgS) is the common ore of mercury.Mercuric chloride is a chemical compound with the formula HgCl2.Mercury oxide is the simple oxide with the formula HgO.Mercury selenide is a chemical compound of mercury and selenium with the formula (HgSe).Note this list of compound of mercury is not exhaustive.
LiCi does not represent a common ionic compound formula. It may be a misspelling or a mistake. However, lithium chloride (LiCl) is a common ionic compound consisting of lithium cations and chloride anions.
The compound of ammonia is NH3. Its scientific name is ammonia, while its common name is also ammonia.
Compounds are recognized from their names by following naming conventions set by the International Union of Pure and Applied Chemistry (IUPAC). The formula provides the specific elements present in the compound and their relative proportions. By understanding common naming rules and analyzing the formula, one can determine the identity of a compound.
No. Compounds have a definite composition, therefore they are pure substances. For example, water always has the formula H2O, sodium chloride (common table salt) always has the formula NaCl, and glucose (blood sugar) always has the formula C6H12O6.
It depends entirely on the configuration and compound. Silicate tetrahedrons (SiO4) are one of the most common cations found in the Earth's crust. Silicon dioxide (SiO2) is one of the most common compounds.
That really depends upon the compound. Since you have not described the compound in any way, there would be no way to work out the formula. Other than that, you are always guided by the periodic table of elements and your knowledge of the valences of the elements; you should be familiar with common radicals, and with various organic compounds which might be part of a formula. The more you know about chemistry, the better chance you will have of working out a given formula.
Sugar, water, and oil are some VERY common compounds.
The common name of this compound is phosphorus pentaoxide and the systematic name is Potassium(V) Oxide.
Aluminum is an element (pure metal), not a compound.
NH3 is formula for a basic compound, Ammonia.NH4+ is formula for a basic cation, Ammonium.