What are examples of a chemical reaction? Select all that apply.
A(2AgI + Na2S → Ag2S + 2NaI
B)4FeS + 7O2 → 2Fe2O3 + 4SO2
C) H2O → SiO2
D)SnO2 → Sn + 2H2O

Determine the wavelength of the light absorbed when an electron in a hydrogen atom makes a transition from an orbital in the n=3 level to an orbital in the n=7 level.

The characteristic of two different types of reactions are shown below. reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of and element. which statement is true about the atoms of the elements that participate in the two reactions? a: their identity changes in both reaction a and b. b: their identity changes in reaction a but not b. c: their identity changes in reaction b but not a. d: their identity remains the same.

How do i turn 2 s into one in the products