Sig Figs/ Theory Pt.1
When do we NOT consider sig figs when making a calculation?
When we use a conversion factor
H2, O2, N2, F2, Cl2, Br2, I2 are all examples of what?
Diatomic Molecule - 2 of the SAME elements together *all examples are found in nature
Do not traverse space and are instead confined to a region *additionally can be used to calculate the location of an electron
Stationary Waves
What occurs when n = infinity
Ionization of an element
True or False: The wavelength and frequency of a wave are inversely proportional
True! In the equation c = wavelength/frequency, c is a constant therefore making wavelength and frequency have an inverse relationship
What are the SF rules when multiplying or dividing numbers?
What did the Gold Foil Experiment prove?
1. Atoms are mostly empty space
2. Most mass is in the nucleus and has a positive charge
What shape to S orbitals have?
Sphere
How are spectral lines generated?
By excitation of electrons and emission of photons
What is the Bohr equation? And what must the element be like in order for us to use it?
E = hv = hc/lamda
Must be "hydrogen like" (only contains 1 electron)
What are the SF rules when adding and subtracting?
The final answer should be the LEAST amount of decimal places as the initial values
Compounds form through the commination of atoms of like elements in WHOLE ratios
Mass %: (Mass of element/Mass of Compound) x 100
Law of Constant Composition
In the Rydberg Balmer Equation, which n value MUST be smaller?
nf MUST be smaller than ni
RZ2((1/nf2)-(1/ni2))
As we go left on the electromagnetic spectrum, what happens to energy?
Energy increases *so does frequency
Equal to the difference between the total nodes and angular nodes ((n-1)-1)
Radial Nodes
Helps us determine the average atomic mass of an element
Mass spectrometry
DOUBLE!!
What changes in an element to make an isotope?
What changes in a element to make an ion?
Isotope: Atoms that vary in neutron count
Ion: Atoms that vary in electron count and have a net charge (Cations = + charged, Anions = - charged)
What happens to energy as redshift(moving away) occurs? And blueshift(moving closer)?
Redshift: Decrease energy
Blueshift: Increase energy
True or False: As n increases, radial nodes decrease
False! Radial nodes increases when n increases
What is the Octet Rule?
Atoms will try to react to gain/lose e- to achieve a full/empty valency
Who believed in these statements?
-Matter consists of indivisible atoms
-All atoms of the same element have the same mass (wrong b/c of isotopes)
-Atoms are the smallest form(wrong because of subatomic particles)
Dalton
Common conversion factor in chemistry with an unusual value
Mol/Avogadro's number
6.02 x 1023 units/ 1 mol
How do you calculate the number of valence electrons?
As we go to the top right of there periodic table, what happens to ionization energy?
Ionization energy increases
DOUBLE: What are the 5 elements that DO NOT follow valence electron rules?
Cr, Mo, Cu, Ag, Au