2. Write the equation for the decomposition of hydrogen peroxide by the action of the catalyst manganese dioxide.
3 Describe the relative solubility of oxygen pas in water. In other words... does it dissolve easily in

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.