Why does a new period start on the periodic table, instead of the row continuing? A. A new period starts when a new energy shell starts. B. A new period starts when a new neutron cycle starts. C. None of these D. It is based on how many protons it has.

B

Explanation:

All the elements in a period have valence electrons in the same shell. The number of valence electrons increases from left to right in the period. When the shell is full, a new row is started and the process repeats.

answer; i believe the correct answer is (solid gold);

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).