Please help it's a select all that apply question I believe and this is also my last attempt I'm a bit confused: Chemistry Entropy

The electron configuration for chromium is 1 s 2 2 s 2 2 p 6 3 s 2 3 p 6 3 d 5 4 s 1 instead of 1 s 2 2 s 2 2 p 6 3 s 2 3 p 6 3 d 4 4 s 1 . the configuration is an exception to the

Which of these would be caused by a chemical change? a) the formation of lava. b) sedimantary rock layering over time. c) metamorphic rock forming from igneous. d) metamorphic rock eroding to form sedimentary rock.

What overall charge must all compounds have