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The formula unit for calcium nitride is Ca3N2. That would be 3 atoms of calcium and 2 atoms of nitrogen, for a total of 5 atoms in a formula unit.
The ions should form CaCl2 because the two chlorine atoms each take an electron from calcium to form the chloride ion Cl-, and the calcium becomes Ca2+ ion.
Calcium chlorate has the formula Ca(ClO3)2. Therefore, there are two chlorine atoms in each formula unit.
There are three atoms in CaCl2 (calcium chloride) - one calcium atom and two chlorine atoms. It might be argued that there are ions inside the molecule instead of atoms. In that case there is one calcium ion and two chlorine ions.
7 atoms.
There is no correct chemical formula described in your question. When calcium and chlorine combine, they form calcium chloride with a formula of CaCl2.
Calcium chloride.
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calcium and chlorine atoms
Chlorine atoms, which are present as chloride ions.
The formula unit for calcium nitride is Ca3N2. That would be 3 atoms of calcium and 2 atoms of nitrogen, for a total of 5 atoms in a formula unit.
Calcium chloride contains only two elements, calcium and chlorine, while calcium chlorate contains these two elements plus oxygen. The chlorine and oxygen in calcium chlorate are combined in a polyatomic ion with formula ClO3-1.
Sodium chloride (NaCl) formula unit has one chlorine atom.
Sodium chloride has two atoms in the formula unit (NaCl): sodium and chlorine.
The ions should form CaCl2 because the two chlorine atoms each take an electron from calcium to form the chloride ion Cl-, and the calcium becomes Ca2+ ion.
Calcium ions have a charge of +2 and chlorine ions have a charge of -1. Because a compound is neutral, you need two chlorine atoms per calcium atom, thus giving us the formula of CaCl2. This tells us that there is one calcium atom in the compound.
Calcium chlorate has the formula Ca(ClO3)2. Therefore, there are two chlorine atoms in each formula unit.