Statement 1: $\mathrm{Si}-\mathrm{Si}$ bonds are much weaker than $\mathrm{Si}-\mathrm{O}$ bonds.

Statement 2: Silicon forms double bonds with itself.

Statement 1:  bond                      bond energy
                        $\mathrm{Si}-\mathrm{Si}$                  297 kJ/mole
                        $\mathrm{Si}-\mathrm{O}$                   464 kJ/mole
Statement 2 : Silicon does not form Si = Si because of larger atomic size.