Gases exert a curtain amount of “pressure” on their container. use any source to define pressure using the behavior of the particles?

The conventional equilibrium constant expression (kc) for the system below is: 2icl(s) ⇄ i2(s) + cl2(g) [cl2] ([i2] + [cl2])/2[icl] [i2][cl2]/[icl]2 none of the listed answers are correct [i2][cl2]/2[icl]

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Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.