Chemistry questions: which of the following is a reasonable ground-state electron configuration?

-1s21p62s22p63s2
-1s22s22p63s23p64s24d8
-1s22s22p63p6
-1s22s22p63s1

Which is true of transition metals when moving from left to right on the periodic table? the d sublevels are not filled across the period. the cation radii become larger across the period. atomic radii increase slightly and then start to decrease. atomic radii decrease slightly and then start to increase. o

Over the last 90 years, scientists have added to the body of evidence supporting the big bang theory. what is the latest piece of evidence discovered in 2014?

Draw the skeletal structures of two different molecules that are each made of 5 carbon atoms and 12 hydrogen atoms.