Cation - a charged ion due to the
of 1 or more electrons
O negatively, loss
O positively, gain
O negatively, gain
positively, loss

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.

Select the correct location on the image identify the element that humans need to breathe. 2015 er r ights reserved

Which best describes the activation energy of a chemical reaction? a. the combined energy of all the reactants b. the amount of energy required for a reaction to occur c. the difference in energy between products and reactants d. the potential energy stored in the bonds of reactants and products