Ch. 6 & 7 atomic structure & periodic trends **test** [100 points] AP Chem

For problems involving calculations, show your work in an organized manner, include any relevant equation (or formula and conversion factor(s)), put the proper units in your calculations / answer, and have the proper number of significant figures in your answer.

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1. Light with a wavelength of 589 nm shone onto a metal caused the emission of electrons, whose kinetic energy is 1.4 * 10^{-19 } J. What is the minimum frequency needed for electron emission in this metal ? [10 points]

2. What is the ___ of the emitted light due to the transition of an electron in the hydrogen atom from n = 4 to n = 1 energy state ? [15 points]

a. energy

b. frequency

c. wavelength

3. What are __all__ possible set of quantum numbers for an electron in the 2p atomic orbital ? Briefly, describe what aspect of an atomic orbital that corresponds to each quantum number. [10 points]

4. Sketch ___ atomic orbital; include the x-, y-, z- axis to show the relationship between these axis and the atomic orbital. [10 points]

a. p

_{x }b. d

_{xy }

5. sketch the orbital diagram of ___; use the noble gas “shortcut” notation. [10 points]

a. oxygen

b. arsenic

6. What is the relative ____ between fluorine versus sulfur ? Justify / rationalize your response. [20 points]

a. atomic size

b. (first) ionization energy

7. Write the chemical equation describing the first-, second-, and third- ionization energy for calcium. [10 points]

8. Justify / rationalize, for calcium: 2nd ionization energy << 3rd ionization energy. [10 points]

9. **old topic**: define “isotope” and provide 2 examples of (reasonable / potential) isotopes. [5 points]

Ch. 6 & 7 atomic structure & periodic trends **retest** [100 points] AP Chem

1. Light with a wavelength of 765 nm shone onto a metal caused the emission of electrons with a kinetic energy of 1.35 * 10^{-19 } J. What is the * range* of wavelength (in meters) needed for electron emission in this metal ? [15 points]

2. In certain situations in the photoelectric effect, the intensity of light does have an effect, while in other situations, the intensity of light has no effect – describe both of these situations. [10 points]

3. rationalize / justify the periodic trend in the (first) ionization energy: [15 points]

a. in general, it increases in a row (left to right)

b. in general, it is relatively stable in the d-block.

c. the exception involving phosphorus and sulfur.

4. write the electron configuration of __ (using nobel gas “shortcut”) and identify the valence and kernel electrons. [10 points]

a. lead

b. strontium

5. lab related questions: justify / rationalize your response. [10 points]

a. Which is the better color, red or blue, to measure the absorption of a red-colored solution ?

b. based on the following hypothetical graph,

what would be the “best” wavelength to use ?

6. electron spin. [15 points]

a. Define “electron spin”

b. relevance to an electron orbital (with respect to the maximum number of electrons in an orbital)

c. relevance to the magnetic properties of an atom ?

7. Pick any 2 of the following choices: describe ___. Clearly identify your choice; will evaluate 2 lowest-scoring choices if you do all three choices. [10 points]

a. aufbau principle

b. Pauli exclusion principle

c. Hund’s rule

8. old topics [15 points]

a. Describe the results of Rutherford’s experiment and its interpretation regarding the atom.

b. For the reaction, H

_{2 }+ O_{2 }--> H_{2 }O, therate = k [H

_{2 }] [O_{2 }]^{1/2 }if the rate is 2.5 μM / second, [H

_{2 }] = 2.0 mM and [O_{2 }] = 5.0 mM, then what is the value and units of the rate constant, k ?