Neon is an element because it is a pure atom
Answer:
H₂S; CO₂; SiH₄
Explanation:
London dispersion forces are larger in molecules that are large and have more atoms or electrons.
A. H₂O or H₂S
H₂S. S is below O in the Periodic Table, so it is the larger atom. Its electrons are more polarizable.
B. CO₂ or CO
CO₂. CO₂ has more atoms. It is also linear, so the molecules can get close to each other and maximize the attractive forces.
C. CH₄ or SiH₄
CH₄. Si is below C in the Periodic Table, so it is the larger atom. Its electrons are more polarizable.
Answer:
12.7mol Na.
Explanation:
Hello there!
In this case, according to the concept of mole, which stands for the amount of substance, we can recall the concept of Avogadro's number whereby we understand that one mole of any substance contains 6.022x10²³ particles, for the given atoms of sodium, we can calculate the moles as shown below:

Thus, by performing the division we obtain:

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