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Chem Unit 2
elements pro/neu/elec, spectrum, valence electrons
Question | Answer |
---|---|
how to find the atomic mass | Average of protons and neutrons |
how to find the atomic mass number | add protons and neutrons together |
why do electrons not count towards the atomic mass? | electron's are so small their weight is insignificant |
how to find the number of neutrons | atomic mass (rounded) - the number of protons |
define an ion | atom with a net electric charge due to the gain or loss of electrons |
how to find the number of electrons | protons minus the charge (divided by -1) |
define atomic mass | the weighted average of all isotopes |
how much is the atomic mass unit in comparison to the carbon-12 atom? | atomic mass unit=1/12th the mass of a carbon 12 atom. (carbon has 6 protons and 6 neutrons) |
how to determine the atomic mass | %=abundance * isotope + %=abundance * isotope =atomic mass (abundance= % in regular number form) |
how to determine which isotope is the most common out of a distribution | go to the periodic table and look at the atomic mass, round it to the isotope that has the nearest number |
what louis de broglie discover | the slower an electron moves and the faster an electron moves, the more it acts like a particle and the more it acts like a wave (respectively) |
what did Erwin schrodinger discover | there are different sizes depending on their energy, and different types of orbitals depending on shape of wavelength |
what are the different letters of the probability clouds | s-clouds=sphere path, p-clouds=double pea in a pod shape (infinity symbol) |
how is the letter of the probability cloud formed | electron runs along the wavelength, then the nucleus in the middle of the wavelength pulls the electron back (- and + charge) |
Heisenburg Uncertainty principle | there is no way to find out the position AND velocity of an electron at the same time. |
what does "v" represent in terms of light waves? | frequency |
define ㅅ | wavelength |
define c | speed of light (3.0x10^8) |
define e | energy |
define h | planks constant (6.626x10^-34) |
equation for frequency | V=c/ㅅ |
equation for energy (2) | E=hv or E= hc/ㅅ |
What causes the light's color to be seen? | phosphorus absorbing UV light and remitting it as visible light. |
What was Bohr's explanation or the atomic spectrum | The energy of an electron depends on its distance from the nucleus. |
ground state | electron is closer to the nucleus; has less energy |
excited state | electron has absorbed energy and moved AWAY from nucleus. |
Does the transition from ground to excited state cause any light to be emitted? | No, it's just like charging a battery |
What is ionization energy | When there is too much energy in an electron , it will pop out of the atomic spectra (therefore meaning no color emitted) |
how many energy rings does s, p, d, and f have? | 1, 3, 5, 7 |
Define electron configuration | The position of an atom's electrons around the nucleus |
What is the Aufbau Principle | Electrons fill orbitals with the lowest energy requirements. each ring=quantum. |
Pauli Exclusion Principle | An orbital will only hold 2 electrons |
what causes the form of the orbitals? | an electron is traveling in a wavelength form and the nucleus that is in the middle of the wavelength pulls the electron back, creating a mirrored path of the electron's original path. |
inside the orbital, what are the two electrons doing? | spinning in different directions, away from each other (opposite charges) |
what causes the two electrons to be a little attracted? | Electrons have opposite poles facing each other, so the poles connect, but that doesn't connect the negative charges. |
Hund's Rule | Each orbital in a sub-level is single occupied before any are doubly occupied. |
millikan discovery | discovered weight of electron and exact charge |
Democritus discovery | said that all thing are made up of their own atoms |
define orbital | area of probability where the electrons are found |