The correct statement about lithium sulfide is:
The atoms in lithium sulfide are held together by bonds.
Here's some clarification on why the other options are incorrect:
- The chemical formula for lithium sulfide is Li2S, not LiS2.
- The statement "Both lithium and sulfur form positive ions" is incorrect. Lithium forms positive ions (Li⁺) while sulfur forms negative ions (S²⁻).
- A molecular model of lithium sulfide would actually have three spheres (two representing lithium atoms and one representing the sulfur atom), not just two.