Asubstance that speeds up the rate of a chemical reaction is called
a. a catalyst.
b. a lipid.
c. a molecule.
d. an element.

What is the polyatamic ion of thiosulfate

Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.

Suppose the universe were completely empty except for one object-a solid sphere moving through space of 100 km/s. what sort of path would the object be moving in? explain your answer