Can y’all me you will mark as brainlist

What happens to energy in an open system?

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

Which type of bonding involves the complete transfer of a valence electron from a less electrogrative atom to a more electronegative one