mass number is the number of protons and neutrons in the nucleus of an isotope . how many protons in an oxygen-18 atom ?

Oxygen - 18 atom contains 8 protons.

Explanation:

The number of protons is the same as the atomic number. In isotopes, only the neutrons vary, but the protons always remain the same.

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 .

the answer is minerals.