Potassium(k) atomic number 19 will most likely react with which of these following elements A sodium (Na) because it is the same Column.

B calcium (Ca because it is in the same row

C chlorine (Ca) because it is a nonmetal

D argon (Ar) because it is a noble gas

Evaporation: this is when warmth from the sun causes water from oceans, lakes, streams, ice and soils to rise into the air and turn into water vapour (gas). water vapour droplets join together to make clouds! condensation: this is when water vapour in the air cools down and turns back into liquid water.

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.

Your question is not clear but if you can explain yourself i would be glad to .  just trying to : ))