How much work is needed to assemble an atomic nucleus containing three protons (such as be) if we model it as an equilateral triangle of side 2.00×10−15m with a proton at each vertex?

3.46 x 10^(-13) Joules

Explanation:

The electrical work needed to assemble the system of three charges can be calculated by the following formula:

Where the variables are draw in teh attached image.

In an equilateral triangle:

r_12 = r_13 = r_23  = r

And all the charges are the same, therefore:

q1 = q2 = q3 = q

Replacing these values in the W formula:

Now let's evaluate this formula with

r =2.00 * 10^-15  m

q = 1.6 * 10^-19 C

freezing

deposition

condensation

explanation;

melting also called fusion is the process where solid becomes liquid, sublimation is the process where solid becomes gaseous without first changing to liquid, deposition involves change from gaseous to solid state, freezing involves change from liquid to solid, boiling or evaporation involves change of liquid to gaseous state, while condensation is the change from gaseous state to liquid state.

endothermic reactions involves absorption of heat from the surroundings or the environment while exothermic reactions involves loss of heat energy to the surroundings.

in this case, sublimation, evaporation and melting are endothermic reactions (gain energy from the environment) while, freezing, deposition and condensation are exothermic (loss of energy to the surroundings) reactions.