Complete the sentence with the word "element" or "compound. O is a(n) and H2O, is a(n)

Element; compound

Explanation:

Oxygen is an element on the periodic table, but when it's combined with the element Hydrogen, it produces water, which is a compound (H2O). When two elements combine, it produces a compound.

I hope this helps! :)

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 .