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| 13435585258 | law of conservation of matter | in chemical reactions matter is neither created nor destroyed | 0 | |
| 13435585259 | law of constant composition | each pure chemical compound always has the same percentage of composition of each element by mass | 1 | |
| 13435586372 | Dalton's atomic theory | 1. All matter is composed of tiny, indivisible parts, called atoms, that cannot be destroyed or created. 2. Each element has atoms that are identical to each other in all of their properties, and these properties are different from the properties of all other atoms. 3. Chemical reactions are simple rearrangements of atoms from one combination to another in small whole-number ratios. | 2 | |
| 13609322710 | law of multiple proportions | When two elements can be combined to make two different compounds, and if samples of these two compounds are taken so that the masses of one of the elements in the two compounds are the same in both samples, then the ratio of the masses of the other element in these compounds will be a ratio of small whole numbers. | 3 | |
| 13609721705 | cathode ray tube | developed in the 1870s by SIr William Crookes who mistakenly thought cathode rays were negatively charged molecules instead of electrons | 4 | |
| 13609775399 | charge to mass ratio | determined by J.J. Thomson for electron (e/m=-1.76X10^8 coulombs gram^-1) by measuring the deflection of the cathode rays in the presence of electric magnetic fields | 5 | |
| 13609788640 | oil drop experiment | performed in 1909 by Robert Millikan from which he calculated the charge of the electron (-1.60X10^-19 coulomb) | 6 | |
| 13609815355 | plum "pudding" model | charge to mass ratio and charge of the electron led to this model of the atom which had electrons in a sea of positive charges; created by J.J. Thomson | 7 | |
| 13609831266 | Ernest Rutherford | identified alpha and beta particles in his research | 8 | |
| 13609841360 | gold foil experiment | performed by Ernest Rutherford along with Hans Geiger and Ernest Marsden, in which heavy alpha particles were aimed at a thin gold foil where most of the alpha particles went through the foil with no visible effect but a few of them were deflected from their path and some actually bounced back in the direction they cam from | 9 | |
| 13609857242 | nuclear model of the atom | based on the results of the gold foil experiment Rutherford deduced this model with an extremely small, dense, and positively charged nucleus surrounded by empty space sparsely occupied by electrons | 10 | |
| 13609892434 | proton | discovered by Rutherford, the basic unit of a positive charge which has the same magnitude of an electron and a mass of 1.67X10^-24 gram | 11 | |
| 13609906631 | neutron | discovered by James Chadwick, the neutral particles in an atom with a mass almost equal to that of the proton | 12 | |
| 13609955334 | solar system model | Niels Bohr completed theory that electrons move around the nucleus in circular orbits | 13 | |
| 13609974987 | wave-mechanical theory | Erwin Schrodinger developed; the position of the electron is described by probability of where it will be located | 14 | |
| 13609994016 | ground state | the lowest possible energy state that an atom (or molecule) usually exists in | 15 | |
| 13609998921 | excited state | a state in which an atom (or molecule) has more energy than the ground state | 16 | |
| 13610023275 | electromagnetic spectrum | 17 | ||
| 13610040480 | c=(lambda)(v) | speed of light=(wavelength in meters)(frequency reciprocal seconds or hertz (Hz)) | 18 | |
| 13610047302 | speed of light (is provided) | 3.0X10^8 m/s | 19 | |
| 13610066666 | Planck's constant (h) (is provided in problem) | 6.63X10^-34 joule second | 20 | |
| 13610074836 | hv=E=h(c/v) | 21 | ||
| 13610127305 | energy of an orbit | En=(-2π^2me^4)/n^2h^2)=-2.178X10^-18/n^2 joule where m = mass of the electron, e = charge on the electron, h = Planck's constant, and n = orbit number (principle quantum number) | 22 |
