4 and 2 electrons are present.
If the moon did not rotate we would see all hemispheres of the moon as it revolves around the Earth and not just the phases.
Liquids stays the same volume but the bonds are spaced out enough that it can take the shape of whatever container it’s in.
Answer:
Individually well, defined identical chemically units such as molecules, ions, atoms, or electrons
Explanation:
The mole is used as the unit of measurement for substance such as molecules, ions, atoms, or electrons. One mole of a substance is equivalent to 6.02×10²³ particles of the substance. The number, 6.02 × 10²³ is known as Avogadro's number.
The particles quantified as moles are individually well, defined identical chemically units such that the mole can be used to describe a part of a substance or the whole substance consisting of several moles of the substance combined.
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>
