Our solar system formed about 4.5 billion years ago from a dense cloud of interstellar gas and dust. The cloud collapsed most likely due to a shockwave form a nearby exploding start called a supernova
Answer:
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Answer:
Yes. Example: <u>Sulfur hexafluoride (SF₆) molecule</u>
Explanation:
According to the octet rule, elements tend to form chemical bonds in order to have <u>8 electrons in their valence shell</u> and gain the stable s²p⁶ electronic configuration.
However, this rule is generally followed by main group elements only.
Exception: <u>SF₆ molecule</u>
In this molecule, six fluorine atoms are attached to the central sulfur atom by single covalent bonds.
<u>Each fluorine atom has 8 electrons in their valence shells</u>. Thus, it <u>follows the octet rule.</u>
Whereas, there are <u>12 electrons around the central sulfur atom</u> in the SF₆ molecule. Therefore, <u>sulfur does not follow the octet rule.</u>
<u>Therefore, the SF₆ molecule is known as a </u><u>hypervalent molecule</u><u> or expanded-valence molecule.</u>
Answer:
In neutralization reaction water and a salt is produced.
A physical change does not change the identity of the substance but the chemical change does.
Example
If you tear or shred a piece of paper it is still paper, but if you pour chemicals on it it will probably change to something else.
