Fecl3 has a RFM of 56 + (35.5 * 3) = 162.5
so find out its moles 16.5 ÷ 162 5 = aprox. 0.1M
then there is a 1 : 3 ratio so 0.1 * 3 = 0.3
then times that by the avogado constant which is 6.02×10^23
0.3 × 6.02×10^23 = ans
hope that helps
I would say when an atom has its valence electron shell filled like a noble gas has, it is not easily changed.
I’m not entirely sure of what you’re asking, but if you’re talking about bonding then it would be an ionic bond that is not easily changed.
Enzymes are organic catalysts
and catalysts generally increase rate of reaction by lowering activation energy
C is the answer