What type of reaction is the following chemical reaction? SeO2 + 3Cl2 -> SeCl6 + O2​

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.

In the cathode ray tube experiment, j. j. thomson passed an electric current through different gases inside a cathode ray tube in the presence of an electric field. in which two ways did this experiment change scientists’ understanding of the atom?

How many neutrons does an element have if its atomic number is 50 and its mass number is 166