Chemistry<span> is often </span>called the central science<span> because of its role in connecting the physical </span>sciences<span>, which include </span>chemistry<span>, with the life </span>sciences<span> and applied </span>sciences<span> such as medicine and engineering.</span>
I believe that you are needing to pick from the three word choices. I believe the first one would be fact and the second one would be conduct experiment.
Answer:
open system
Coffee held in a cup is an open system because it can exchange matter water vapors and energy heat with the surroundings.
Answer:
1
Explanation:
I would say 1 because that configuration has 7 valence electrons. The goal of the atom is to gain a full octet so it just needs to gain 1 more electron to get the full octet. To get the one electron to fill the valence shell it would only need to have 1 covalent bond.
I hope this helps. Let me know if anything is unclear.