Which of the following is true about the Lewis structure of NF3? -26 valence electrons have to be accounted for in NF3
-There are single covalent bonds between N and F
-The N atom is less electronegative than the F and so occupies the central position in the skeletal structre
-All of the above

Use the periodic table to determine the electron configuration of dysprosium (dy) and americium (am) in noble-gas notation.

Astudent is asked to identify and element that is pale yellow brittle solid and does not conduct electricity. at which location in this periodic table would the element most likely be found?

What amount of heat is exchanged when 106.2 grams of substance y goes from a liquid at 35 degrees celsius to a solid at the same temperature? melting point of substance y = 35 degrees c; δhvaporization = 3.67 j/mol; δhfusion = 3.30 j/mol. mwsubstance y = 28.22 g/mol. −12.4 j −3.51 x 102 j 1.24 x 101 j 351 j