Chapter 1 - Atomic Structure

Question 1

what was the significance of Rutherford?

Answer 1

provided evidence that atom has a dense, positively charged nucleus that accounts for only a small amount of the atom’s volume

Question 2

why was Plank significant?

Answer 2

developed first quantum theory, proposed that energy emitted as electromagnetic radiation from matter comes in discrete bundles called quanta

Question 3

what is the equation for the energy of a quanta?

Answer 3

E=hf

Question 4

what did Bohr propose?

Answer 4

that the hydrogen atom consisted of a central proton around which an electron traveled in a circular orbit; centripetal force acting on electron was created by electrostatic force between proton and electron; placed restrictions on angular momentum

Question 5

what is the equation for angular momentum?

Answer 5

L=nh/2π

Question 6

what is the equation for the energy of an electron?

Answer 6

-Rh/n^2

Question 7

what does a value of zero energy mean for an electron?

Answer 7

the electron and proton are separated completely, no attraction

Question 8

what is the relationship between energy of an electron and distance from nucleus

Answer 8

energy of an electron increases (becomes less negative) the further out from the nucleus it is located; energy always changes in discrete amounts

Question 9

what is the ground state of an atom?

Answer 9

state of lowest energy (n=1), smallest radius

Question 10

what is the excited state of an atom?

Answer 10

occurs when an electron is promoted to an orbit with a larger radius (higher energy)

Question 11

how are electrons excited to a higher state?

Answer 11

heat or other energy forms, must have an energy input exactly equal to the difference in energy from one orbital to another so electron can ‘jump’ to higher-energy state

Question 12

what happens when electrons return to ground state?

Answer 12

emission of photons in discrete amounts of energy equal to the difference in energy between orbitals

Question 13

what is the equation for the energy of a photon?

Answer 13

E=hc/λ

Question 14

what is a line spectra of an atom?

Answer 14

spectrum composed of specific frequencies, each line corresponds to specific electron transition

Question 15

what is an atomic emission spectrum?

Answer 15

Each element can have its electron excited to different sets of distinct energy levels, therefore each possesses a unique atomic emission spectrum, can be used as a unique fingerprint for the element

Question 16

what is the Lymann series?

Answer 16

group of hydrogen emission lines corresponding to transitions from energy levels n≥2 to n=1

Question 17

what is the Balmer series?

Answer 17

group of hydrogen emission lines corresponding to transitions from energy levels n≥3 to n=2

Question 18

what is the Paschen series?

Answer 18

group of hydrogen emission lines corresponding to transitions from energy levels n≥4 to n=3

Question 19

what is the equation for the energy associated with a change in quantum number?

Answer 19

E=hc/λ=-RH (1/(ni^2 )-1/(nf^2 ))

Question 20

what is an absorption spectrum?

Answer 20

When an electron is excited to a higher energy level, it must absorb the exact amount of energy to make that transition, results in energy absorption of specific wavelengths; Every element possesses a unique absorption spectrum