What element forms an ion with an electronic configuration of [ne] and a –2 charge?

All of the following are part of the biosphere except

The twister and runaway train are two coasters at the same amusement park. both coasters start at the same height. the coaster for the twister is twice the mass of the coaster for the runaway train. which roller coaster has greater gravitational potential energy at the start of the ride?

Which statement describes the phase change that occurs when dry ice is placed in an open container at room temperature?