Chemistry Basics
How many significant figures are there in the following number: 00203.2410
7
Hassium-277 undergoes alpha decay. What is the resulting new atom with atomic mass?
Seaborgium(Sg)-273
This scientist used oil drops to discover what? Give the name and discovery. (just last name is ok)
Robert A. Millikan; charge of an electron
Are infrared waves harmful to humans?
No, they are placed after the visible light region on the EM spectrum, indicating they have a larger wavelength. Higher wavelength means less energy so not harmful.
What shape is the s orbital?
Sphere
Complete the following problem with the correct amount of sig figs: (3.4590*2.2 + 02.334)/1.93
5.1
Radon-222 is formed after an atom undergoes B- emission. What was the initial atom? (you must answer with atomic mass)
Francium-222
The fact that cathode rays can be developed from different types of atoms established what?
All atoms have electrons.
Who came up with an equation that related a particle's wavelength to its mass? What was his equation?
De Broglie wave equation
lambda = h/mv; v = velocity
The following electron configuration violates which fundamental of electron behavior?
1s22s23p4
Aufbau Principle - electrons fill lower energy orbitals first before moving onto higher energy orbitals.
In this case, this configuration suggests that the electrons will fill into the 3p orbitals without filling lower energy 3s orbitals.
(Note: this configuration is possible if the electrons are excited, but violates the Aufbau principle in ground state)
Pd-112; 64 neutrons
What happens to the energy of an electron as it jumps further away from its atomic nucleus? (You must state the type of energy being affected)
Potential Energy Increases
They are affected by electromagnetic energy aka light.
They contain a charge and a magnetic field.
They behave like particles and waves.
They contain a quantifiable spin.
(any one of these is fine)
My monitor has a refresh rate of 144hz. That means it emits a new image 144 times per second. What would be the energy of a wave that had the same frequency?
9.54 x 10-32 J
Define degeneracy. What is the degeneracy of p orbitals?
Degeneracy is the idea that certain orbitals can be equal in energy so that electrons can occupy any one of those orbitals at an equal energy state.
The degeneracy of p orbitals is 3. This means there are always 3 equal energy suborbitals called px, py, pz
Which is greater by mass? 5.42 mol K or 1.7 mol Te?
1.7 mol Te = 220 g Te
Bismuth-210 is formed after an atom undergoes alpha decay and subsequent B+ emission. What was the initial atom? (answer with atomic mass)
Radon-214
If the nucleus of an atom were NOT centrally concentrated but, scattered throughout the atom, as was discovered by this scientist, what would he have observed? Name the scientist, brief summary of his experiment, and answer the question.
Rutherford; shot alpha particles through gold foil onto radiosensitive film.
He would have seen total deflection a lot more frequently, with minimal amount of particles of making it through the foil.
A wave emitted by an electron transitioning down energy levels has energy 4.67 x 10^-24 J. What is the idea that electron exists in whole number energy levels called? What is the frequency and wavelength of that wave?
Quantization
7.05 x 10^9 hz; 0.0425 m
Place the following orbitals in increasing order based on energy: 3d, 4f, 6s, 5p. Answer with the maximum number of electrons that can be held in each orbital.
3d10, 5p6, 6s2, 4f14
82 = Pb, Lead
Why is electron capture a favorable method of nuclear decay?
Place the following scientists in chronological order based on how their discoveries helped shape the modern atom: Rutherford, Bohr, Thomson, Chadwick.
Thomson, Rutherford, Bohr, Chadwick.
1.260 x 10^6 J
What is the electron configuration for a neutral, ground state Ag atom.
1s22s22p63s23p64s23d104p65s14d10 or [Kr]5s14d10
Partial credit for:
1s22s22p63s23p64s23d104p65s24d9 or [Kr]5s24d9