Na₂CrO₄ + PbCl₂ → PbCrO₄ + 2 NaCl
<u>Explanation:</u>
In a double displacement reaction, the reactants which are involved in the reaction exchanging their ions thereby produces 2 new compounds. Here sodium chromate and lead chloride are undergoing double displacement reaction, the ions exchanges their position there by forming sodium chloride and lead chromate. So the double displacement reaction is given as,
Na₂CrO₄ + PbCl₂ → PbCrO₄ + 2 NaCl
Democritus *suggested* the existence of the atom, that everything was made up of tiny particles, but wasn't really able to get more specific than that. Dalton also theorized that everything was made up of indivisible particles, but went further basing his theory on actual scientific principles, such as the Law of Conservation of Mass and the Law of Constant Composition. He also said that atoms weren't created or destroyed in a chemical reaction, just rearranged. There's more to it than that, but basically, Dalton's theory was based more on science while Democritus' theory was too general to be useful in chemical situations.
Answer:

Explanation:
Oxygen has eight eletrons and six valence electrons, giving it the electron configuration of
.
Erosion? As time passes, the continents move? Some crumble? I don't know but I tried