<span>The oldest of those supercontinents is called Rodinia and was formed during Precambrian time some one billion years ago. Another Pangea-like supercontinent,
Pannotia, was assembled 600 million years ago, at the end of the
Precambrian. Present-day plate motions are bringing the continents
together once again.</span>
Answer:
The reaction combines the sodium with the hydrogen and oxygen in water to form sodium hydroxide and hydrogen gas, and you get a lot of energy released as heat as well. This heat actually melts any remaining sodium that has not reacted yet, and ignites the hydrogen gas, so you get the bang and the flash.
Explanation:
<span>If two fluorine atoms bonded with each other what kind of bond would be involved?
A. ionic
B. valence
C. covalent
D. non-metallic
C. covalent
</span>
D
A- Harvard university professor
