Complete and balance the following equation:

S + OH^- $$\to$$ S^2- + $$S_2O_3^-$$

Complete and balance the following equation:

Ag⁺ + AsH₃ $$\to$$ H₃AsO₃ + H⁺

Arrange the following in increasing oxidation number of iodine.

I₂, HI, HIO₄, ICl

The electron density in the XY plane in 3d_{x² - y²} orbital is zero