What is the percent by mass of oxygen in sodium hydroxide?

What will most likely happen when two bromine atoms bond together?

Phosphorous can form an ion called phosphide, which has the formula p3−. this ion can form an ion called phosphide, which has the formula p3−. this ion properties very similar to those of pforms when a phosphorus atom loses three protonsis called a cationcontains 18 electrons

What is the value of the standard enthalpy of formation of an element in its most stable form?