13. Nt
14. St
15. St
16. At
17. Nt
Measure which mass? I recommend editing the question so that I can answer it and get more points >:)
Answer:
Each principal energy level above the first contains one s orbital and three p orbitals. A set of three p orbitals, called the p sublevel, can hold a maximum of six electrons. Therefore, the second level can contain a maximum of eight electrons - that is, two in the s orbital and 6 in the three p orbitals.
Explanation:
Answer:
<em><u>Over 96 percent is saline. Of total freshwater, over 68 percent is locked up in ice and glaciers. Another 30 percent of freshwater is in the ground.</u></em>