Two highly reactive elements in period 2 are the metal lithium an the A)metaloid
B)nonmetal selenium
C)nonmetal fluoride
D)nonmetal krypton

fire could start, buildings collapsing, and ash falling from the sky.

explanation:

this is because the buildings or plants could catch on fire and the buildings would most likely collapse. lastly ash would fall because all the burning would cause ash to fall from the sky.

hope this .