The correct statement about lithium sulfide is: The atoms in lithium sulfide are held together by bonds.
Here's why the other statements are incorrect:
-
The chemical formula for lithium sulfide is LiS2. - This is incorrect. The correct chemical formula for lithium sulfide is Li2S, indicating two lithium atoms for every one sulfur atom.
-
A molecular model of lithium sulfide would have two spheres. - This is misleading. While a model might show two lithium atoms and one sulfur atom, it would actually represent three spheres in total (two for lithium and one for sulfur).
-
Both lithium and sulfur form positive ions. - This is also incorrect. Lithium (Li) forms a positive ion (Li⁺), but sulfur (S) typically forms a negative ion (S²⁻) in ionic compounds like lithium sulfide.
Thus, the most accurate statement is about the presence of bonds holding the atoms together in lithium sulfide.