What is the hydronium ion concentration, [H3O+] of a 5x10^-4 M solution of NaOH?

50 pts plz what is the physical state of matter of baking soda.

An atom of which element reacts with an atom of hydrogen to form a bond with the greatest degree of polarity ?

The bond energy for the van der waals bond between two helium atoms is 7.9×10−4ev. assuming that the average kinetic energy of a helium atom is (3/2)kbt, at what temperature is the average kinetic energy equal to the bond energy between two helium atoms