Final answer:
The balanced chemical equation for the reaction between cesium and selenium to form cesium selenide is 2Cs + Se → Cs2Se.
Step-by-step explanation:
The balanced chemical equation for the reaction between cesium and selenium to form cesium selenide is:
2Cs + Se → Cs2Se
In this reaction, 2 atoms of cesium combine with 1 atom of selenium to form 1 molecule of cesium selenide.