When aqueous solutions of lead(II) nitrate and potassium iodide are mixed, a bright yellow solid forms and settles out of the liquid.
Which observation MOST STRONGLY supports that a chemical change has occurred?
a) The total mass of the closed system is conserved throughout the process.
b) The mixture becomes opaque due to suspended solid particles.
c) A precipitate forms, indicating creation of a new compound with different composition.
d) The temperature of the mixture remains nearly constant during mixing.