Chem 101 Drexel Final GRADE A+ GURANTEED CORRECT

matter everything states of matter solid liquid gas plasma 10 Must-Have Accessories for Sprucing Up Your Caravan homogeneous uniform throughout heterogeneous not uniform throughout law of constant composition all samples of a given chemical compound have the same elemental composition by mass law of multiple proportions elements combine in small whole number ratios to form compounds law of conservation of mass total amount of mass remains constant Dalton's law in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases structure of the atoms Atoms consist of electrons surrounding a nucleus that contains protons and neutrons electrons negative subatomic particles surrounding the nucleus in a cloud neutrons non-charged subatomic particle in the nucleus protons positive charged subatomic particle in the nucleus atomic number the number of protons mass number the total number of protons and neutrons isotopes different mass number, becasue thenumber of nucleons (both protons and neutrons) in the nucleus is the atom's mass number atomic mass units a unit of mass used to express atomic and molecular weights atomic weight the average of the isotope weights weighted for the isotope distribution mass spectrometer an instrument which can measure the masses and relative concentrations of atoms and molecules cathode tube experiment a phosphor-coated glass tube from which the air has been removed, two electrodes, negative electrode, positive electrode. When a high voltage electrical current is applied between the electrodes, a cathode ray travels from + to -, produces green light, discovered electrons oil drop experiment measured the charge of an electron using oil and 2 pieces of metal scattering of alpha particles projected alpha particles against hydrogen protons, learned about the structure of atoms mass to moles divide by molar mass moles to mass multiply by molar mass moles to molecules multiply by avogadro's number molecules to moles divide by avogadro's number accuracy closeness of a measured value to a standard or known value precision closeness of two or more measurements to each other intensive properties doesn't change when you take away some of the sample extensive properties changes when the size of the sample changes potential energy has the potential to be converted into other forms of energy kinetic energy energy an object possesses due to its motion work energy required to move an object against a force (joule) avogadro's number 6.022×10^23 moles substance is called the molar mass of that substance sig figs how many digits you use, and how to round correctly scientific notation the way that scientists easily handle very large numbers or very small numbers density p=M/V Electromagnetic radiation the radiant energy released by certain electromagnetic processes wavelength the distance between successive crests of a wave frequency the number of occurrences of a repeating event per unit time energy of photons E = hc/lamda (energy = Planck constant*speed of light / wavelength) photoelectric field wave like properties of small particles every elementary particle or quantic entity exhibits the properties of not only particles, but also waves DeBroglie equation lamda = h/MV (wavelength = Planck constant/ mass*velocity) atomic spectra the spectrum of frequencies of electromagnetic radiation emitted or absorbed during transitions of electrons between energy levels within an atom energy levels of electrons in atoms the energy levels filled depends on the amount of electrons in the atom heisenberg uncertainty principle the more precisely the position of some particle is determined, the less precisely its momentum can be known quantum numbers n, l, and m, that describe an orbital n any whole number, 1, 2, 3, etc l 0 to n-1 m(sub)l -l to l m(sub)s +1/2 or -1/2 orbitals s, p, d, f s 1st orbital (alkaline earth and alkali) p CONTINUED......