Borek said:This is not an oxoanion.
Besides, it happens that calcite is a (historical) name of mineral - calcium carbonate.
Ok there is another part of the problem and it is name the following compound PbCrO4. It says the answer is lead(2) chromate. Why would it be this answer because this shouldn't be a oxyanion either? Why wouldn't it be lead chromium oxide?Borek said:CaO has no charge.
Borek said:This is a completely different compound - and it is a salt, made of lead(II) (Pb2+) and chromate anion (CrO2-). CrO2- is an oxyanion (and has a charge, which in a compound is neutralized by the opposite charge of lead, yielding PbCrO4).
Note that the first compound contained only one metal (Ca) combined with oxygen, the latter contains two metals (Pb and Cr) - that's a strong hint it is not a simple oxide.
In an ionic compound, the cation is always written first and the anion is written second. This is because the cation, which is a positively charged ion, is attracted to the anion, which is a negatively charged ion. For example, in the compound NaCl, sodium (Na) is the cation and chloride (Cl) is the anion.
The general rule for naming an ionic compound is to write the name of the cation followed by the name of the anion. However, if the anion is a nonmetal, the ending of its name is changed to "-ide". For example, the compound NaCl is named sodium chloride.
Some common polyatomic ions found in ionic compounds include hydroxide (OH-), ammonium (NH4+), carbonate (CO32-), and sulfate (SO42-). These polyatomic ions have multiple atoms bonded together and have a charge that helps to determine the overall charge of the ionic compound.
The charge of a transition metal in an ionic compound can be determined by referring to the periodic table. The charge of a transition metal can vary, but it is usually indicated by a Roman numeral in parentheses following the name of the transition metal. For example, Fe(III) represents iron with a charge of +3.
Yes, an ionic compound can have more than one cation and anion. This is known as a polyatomic ionic compound. The name of the cation and anion in a polyatomic ionic compound are written in the same order as in a simple ionic compound, but the names of the polyatomic ions are not changed to "-ide". For example, the compound Ca(OH)2 is named calcium hydroxide.