Which choice best compares these two observations? A) Observation 1. describes a physical change, and Observation 2 describes a
chemical change.
B В
Observation 1 describes a chemical change, and Observation 2 describes a
physical change.
Each observation describes a physical change.
D Each observation describes a chemical change.

Harvey mixes two liquids. which observation of the new mixture most likely indicates a precipitate is forming?

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.

What’s the theoretical yield of solid lead