When two atoms of the same element are covalently bonded, the radius of each atom will be half the distance between the two nuclei because they equally attract the electrons. The reason for this trend is that the bigger the radii, the further the distance between the two nuclei. Hope this helps:)
Explanation: <em>The hypothesis is a prediction, but it involves more than a guess. Most of the time, the hypothesis begins with a question which is then explored through background research. It is only at this point that researchers begin to develop a testable hypothesis.</em>
(Unless you are creating an exploratory study, your hypothesis should always explain what you expect to happen)
The element cobalt can form compounds in two different oxidation states, +2 and +3.
The +2 state is more common.
The ion Co2+ (aq) is pink.
Other compounds of cobalt(II), which include both anhydrous Co2+ and complex ions, are commonly blue.
If an aqueous solution contains both cobalt(II) and chloride ions, the blue ion CoCl42- forms, in equilibrium with the pink Co2+ (aq) ion.
<span>CoCl42- (aq) <===========> Co2+ (aq) + 4Cl1-(aq)</span>
