Answer:
Boron and Aluminum
Explanation:
If you write the electron configuration for boron and aluminum, you get:
for boron and 
for aluminum. Both have 3 valance electrons and has 2 electrons in a s-orbital and 1 in a p-orbital. These valance electron similarities are based on the column/group the elements are. Therefore, Boron and Aluminum have similar chemical behaviours and similar arrangement of outer/valance electrons.
What does it happen in smallest scale?
<span>You have to look for "DUPRE' EQUATION" which treat about </span>
<span>"TWO-PHASE INTERFACIAL FORCEs". </span>
<span>At boundary surface between two aggregation phases, you may attribute upper energy level to molecules standing at the boundary zone. So, it has to define INTERFACIAL FORCEs WHICH ACT TO REMODEL SHAPE AND EXTENSION OF MEETING PHASEs. </span>
<span>In your case, Water's Droplet is a liquid phase surrounded by Air (e.g. gas phase) and Interfacial Forces act to dominate Boundary-Surface. </span>
<span>Mathematically, smallest possible Surface comes to SPHERICAL SHAPE. </span>
Answer: precipitate.
Explanation:
1) When the product of the reaction between the chemicals in the solution is insoluble, then it cannot remain in the solution and it will precipiate, forming a solid substance.
2) That happens, for example, when you have two solutions with different solutes, mix them together, the solutes can react chemically with each other, yielding a product that is insoluble.
3) A typical example of such kind of precipitation reactions is athe neutralization of an acid and a base.
Acid + Base = salt + water
If the salt is insoluble in water then it will form a a precipitate (solid), if the product is soluble in water then it remains as an aqueos ions in the solution.
