Asolution is formed when the solute uniformly disperses throughout (or dissolves in) the solvent. the process can be described by three steps:

1. separation of solvent-solvent particles (aka expanding the solvent),

2.separation of solute-solute particles (aka expanding the solute), and

3. formation of solute-solvent interactions.

classify the steps involved in the formation of a solution as being endothermic or exothermic.

a. step 1 is exothermic, step 2 is exothermic, step 3 is endothermic

b. step 1 is endothermic, step 2 is endothermic, step 3 is exothermic

c. step 1 is endothermic, step 2 is exothermic, step 3 is exothermic

d. step 1 is exothermic, step 2 is endothermic, step 3 is exothermic

B. Step 1 is endothermic, Step 2 is endothermic, Step 3 is exothermic

Explanation:

Prior to the formation of a solution, the solvent molecules attract each other as well as the solute molecules. For a dissolution to be effective, those interactions need to be weakened, at the same time that interaction between solute and solvent ought to be established. The formation of solute-solvent interactions is exothermic and provides the energy required to separate solvent-solvent particles and solute-solute particles, being both processes endothermic (the absorbed energy is used to break the interactions).

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.