Match the scientist to his contribution to the atomic theory. (4 points) 1. John Dalton 2. Niels Bohr 3. Ernest Rutherford 4. J. J. Thomson a. Electrons are scattered within the atom. b. Atoms are the smallest unit of an element. c. Protons are at the center of an atom. d. Electrons are in orbital levels.

chemical digestion occurs in the stomach were hcl and pepsin forms chyme, the mouth in which salivary amylase breaks down starch to form bolus, and the small intestine specifically the duodenum.

elements make up everything, and they combine to make compounds.

the answer is c

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.