Question

When metals react with nonmetals, an ionic compound generally results. What is the predicted general formula for the compound formed between an alkali metal and sulfur? Between an alkaline earth metal and nitrogen? Between aluminum and a halogen?

Answer 1

The general formulas for the compounds formed between an alkali metal and sulfur, an alkaline earth metal and nitrogen, and aluminum and a halogen are M2S, M3N2, and AlX3 respectively, where M represents the metal and X represents the halogen.

Step-by-step explanation:

When metals react with nonmetals, the result is generally an ionic compound. For an alkali metal reacting with sulfur, the alkali metals (Group 1) typically form +1 cations. Therefore, since sulfur tends to form a -2 anion (S2-), the expected formula would be M2S, where M represents the alkali metal.

Between an alkaline earth metal and nitrogen, alkaline earth metals (Group 2) typically form +2 cations, while nitrogen tends to form a -3 anion (N3-). Therefore, the general formula for the compound formed in this case would be M3N2, with M representing the alkaline earth metal.

For aluminum, a Group 13 element, it typically forms a +3 cation (Al3+). When reacting with a halogen, which forms a -1 anion, the resulting compound would have the formula AlX3, where X represents the halogen.

Answer 2

Ionic compounds are formed when metals react with nonmetals, with alkali metals and sulfur forming M2S, alkaline earth metals and nitrogen forming M3N2, and aluminum and halogens forming AlX3.

Step-by-step explanation:

When metals react with nonmetals, ionic compounds are typically formed due to the transfer of electrons. For each pair of reactants mentioned, the general formula of the resulting compound can be predicted based on the charges of the ions each element typically forms.

An alkali metal (from Group 1 of the periodic table) reacts with sulfur to form a compound with the formula M2S, where M represents the alkali metal. This is because alkali metals form +1 ions and sulfur typically forms a -2 ion.

An alkaline earth metal (from Group 2) reacts with nitrogen to form a compound with the formula M3N2, where M represents the alkaline earth metal. Alkaline earth metals form +2 ions and nitrogen typically forms a -3 ion, thus two metal ions are needed for three nitrogen ions to maintain charge balance.

Aluminum, which typically forms a +3 ion, reacts with a halogen to form a compound with the formula AlX3, where X represents the halogen. Halogens form -1 ions, therefore three halogen ions are needed to balance the +3 charge of the aluminum ion.