Given the equations and the values of AH' for the combustion of CH (9) and the combustion of C(graphite) represented above, which of the following additional information is needed to determine the values of AH' for the overall reaction 2 C(graphite) + 3 H2(g) → C2H6(g)?

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

Which statement would indicate the presence of an acid

What is the largest environment on earth?