CLEP Chemistry questions well answwred graded A+ 2023

CLEP ChemistryJohn Dalton - correct answer Proposed that matter is composed of atoms; these atoms have different identities called elements, which combine to form compounds; measured masses of reactants and products. J.J. Thompson - correct answer Observed deflection of particles in a cathode ray tube; proposed that atoms are composed of positive and negative charges; developed the plum pudding model of the atom Robert Millikan - correct answer Calculated the charge-to-mass ratio of electrons using oil drops falling in an electric field; surmised the charge of a single electron Ernest Rutherford - correct answer Used the deflection of alpha particles in a cathode ray tube to discover that most of the atom is empty space, with protons and neutrons centered in the nucleus. Niels Bohr - correct answer Determined that electrons exist around the nucleus at a fixed radius; electrons with higher energy exist farther from the nucleus. Electrons give off electromagnetic radiation when moving between energy levels. Max Planck - correct answer Determined that energy is quantized, or composed of discrete bundles. 6.63 x 10^-34 J*sec - correct answer Planck's Constant (h) 3.00 x 10^8 m/sec - correct answer Speed of Light (c) E = hv - correct answer Energy of a Photon Formula (1) E = hc / wavelength - correct answer Energy of a Photon Formula (2)