6) A student performed an analysis of a sample for its calcium content and got the following results: 14.92%, 14.91%, 14.88%, 14.91%
The actual amount of calcium in the sample is 15.70%. What conclusions can you draw about the accuracy and
precision of these results?

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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~ trueboss72