Name the two types of sub-atomic particle in the nucleus of an atom.

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.

Which of the following is a pure substance? airbloodcopperwood

Equal volumes of h2 and o2 are placed in a balloon and then ignited. assuming that the reaction goes to completion, which gas will remain in excess? 2h2 + o2 → 2h2o a. both are in equal proportion b. oxygen c. water d. hydrogen