Topic 2: Atomic Structure Flashcards
What did Rutherford’s experiment consist of? What did Rutherford’s experiment determine?
Particle deflection. Determined that atoms are mostly empty space and that they have nuclei.
In nuclear notation, which numbers go where to represent atomic number, mass, and charge?
Mass number=upper left, atomic number=lower left, charge=upper right
Carbon 14 is a radioactive isotope. What is carbon 14 used for?
Carbon dating, cancer treatment
Cobalt-60 is a radioactive isotope. What is it used for? What type of radiation does it emit?
It emits gamma and is used to treat cancer, to stop an immune response to transplanted organs, and to sterilize foods.
Iodine-131 emits what kind of radiation? What is it used for?
Beta and gamma, to treat thyroid cancer.
Iodine-135 emits what kind of radiation and is used for what?
Emits gamma, treats prostate cancer and brain tumors.
Radioisotopes refers to…
radioactive isotopes
What do mass spectrometers do?
They measure the individual masses of atoms.
What are the 5 steps in the process of mass spectrometry?
Vaporization of the sample to separate particles, ionization of the atoms through e- bombardment to leave them with +1 charge, acceleration of ions thru a tube, deflection of ions through magnetic field, detection of ions measuring their location and # of particles.
Why is the deflection step so important in mass spectrometry?
Ions are deflected more or less depending on their absolute mass, charge, velocity, and the strength of the magnetic field. This step is shows as mass spectrum.
Describe the features of a mass spectrum graph.
Y-axis=percent abundance, x-axis=relative isotopic mass. You can determine the percent abundance of certain isotope groups. The number of peaks is the number of different isotopes.
How do you calculate relative atomic mass?
(isotopic mass 1 x %abundance as a decimal) + (isotopic mass 2 x %abundance as a decimal)…
What is the big important feature of the Bohr model?
It shows orbitals of differing energy as energy levels
What 4 concepts does the Bohr model support?
Electrons orbiting at fixed levels, orbitals further from nucleus are higher energy, electrons are quantized, electrons can only jump 1 orbital at a time.
What does it mean that electrons are quantized? What is ground state?
They can only be in one energy level or another, not in between. The ground state refers to their normal energy level.
What could Bohr not explain with his model?
Why only certain energy levels were allowed.
What causes emission spectra to be produced?
When e- emit photons as they transition from a higher to a lower energy level. Each transition corresponds to a specific wavelength and frequency.
Emission spectra can help scientists….
Identify an unknown element.
Line spectra only contain…
specific colors of visible light
Spectra that are not line spectra are…
continuous, containing all colors
What is proof that electrons exist in discrete energy levels?
The Hydrogen emission line spectrum
What is the Balmer series?
When an e- drops from a higher energy level to n=2. Visible light is emitted.
What is the Lyman series?
Electron transition to n=1. UV light emitted.
What is the Paschen series?
Electron transition to n=3. IR light emitted.
True or false: All electromagnetic waves travel at the same speed.
True. The speed of light is a constant.
If all electromagnetic waves travel at the same speed, how can they be distinguished?
By their wavelengths (lamda symbol), which is the distance between two crests of the wave.
What are the relationships between wavelength, frequency, and energy?
Higher frequency=higher energy=smaller wavelength because there are more waves per second. Lower frequency=lower energy=larger wavelength.
What does the Electromagnetic spectrum show?
Range of all possible EM radiation frequencies.
List the types of electromagnetic radiation in increasing order of energy.
Radio, microwave, IR, visible, UV, X-ray, gamma
What does Heinsenberg’s Uncertainty Principle state?
It is impossible to exactly locate an electron
What is an orbital?
A region with at least a 95% chance of finding an e-
How many e- can ea. orbital hold?
2 max
If there are 2 e- in one orbital, how do they spin?
Opposite spins.
What is the Pauli exclusion principle?
Ea. orbital can hold 2e- max, with opposite spins.
What is the Aufbau principle?
Electrons fill the lowest energy orbitals first.
What is Hund’s Third Rule?
Orbitals are filled singly first, then doubly.
Each energy level (n=1, n=2, etc.) is divided into…which have a fixed number of…
Each energy level is divided into sublevels spdf with a fixed number of orbitals
What is a sublevel?
A group of orbitals w/ particular properties
The s sublevel has what shape, how many orbitals, can hold how many e-?
Sphere, 1 orbital, 2 e- max
The p sublevel has what shape, how many orbitals, can hold how many e-?
Dumbell, 3 orbitals, 6 e- max
The d sublevel has how many orbitals, can hold how many e-?
5 orbitals, 10 e- max
The f sublevel has how many orbitals, can hold how many e-?
7 orbitals, 14 e- max
What is the formula for determining how many e- each energy level can hold?
2 x (n^2)
What does electron arrangement refer to?
The number of e- per each main energy level
Four things to consider when writing e- configurations:
1) determine total # of e-
2) Fill lowest energy sublevels first
3) 4s is filled before 3d and removed before 3d
4) Condensed e- configurations use the last noble gas as a placeholder
What is the e- config for Copper Cu?
[Ar] 3d^5 4s^1
What is the e- config for Chromium Cr?
[Ar] 3d^10 4s^1