While preparing his garden for spring planting, Brian grabs a shovel that was left outside all winter. He notices its metal component is covered in a red substance. What question can Brian ask to determine if the red substance indicates a chemical or physical reaction?

Moles = mass/molar mass the molar mass of c20 = 12.011*20 = 240.22 g per mole therefore, the number of moles is 20 g / 240.22 g per mol = 0.0833 moles.

The correct answer is:   [a]:   the "stratosphere" .

Small amounts of matter are converted intolarge amounts of energy occurs in both fusion and fission reactions. they are nuclear reactions where a change in the identity or characteristics of an atomic nucleus results when it is bombarded with an energetic particle, as in fission, fusion, or radioactive decay.