Step 1: Draw the Lewis structure of H\_2Se. Selenium (Se) is the central atom bonded to two hydrogen (H) atoms, and it has lone pairs of electrons.
Step 2: Determine the molecular geometry using the VSEPR theory. Selenium has 6 valence electrons, two of which form bonds with hydrogen atoms, leaving two lone pairs on Se. This results in a bent molecular shape similar to H\_2O.
Step 3: Consider the electronegativity difference between Se and H. Selenium is more electronegative than hydrogen, so the Se-H bonds are polar with a dipole moment pointing toward Se.
Step 4: Analyze the molecular shape and bond dipoles. Because the molecule is bent, the bond dipoles do not cancel out, resulting in a net dipole moment.
Step 5: Conclude that due to the bent shape and polar bonds, H\_2Se is a polar molecule.