MCAT General Chemistry Review: Chapter 1

Question 1

Orbitals

Answer 1

Electrons move rapidly and are localized within regions of space around the nucleus called orbitals

Question 2

Heisenberg Uncertainty Principle

Answer 2

It is impossible to simultaneously determine, with perfect accuracy, the angular momentum and position of an electron

Question 3

Four quantum numbers

Answer 3

n, l, m_l, m_s

-=subscript

Question 4

Avogadro’s number

Answer 4

6.02 x 10^23

The atomic weight of carbon is 12.0 amu. The average carbon atom had a mass of 12.0 amu and 6.02 x 10^23 carbon atoms have a combined mass of 12.0 grams.

Question 5

Quanta

Answer 5

Energy emitted as electromagnetic radiation from matter comes in discrete bundles.

Discrete bundles of energy in the form of electromagnetic radiation

Question 6

Planck relation (energy of a quantum)

Answer 6

E=hf

Question 7

Plancks constant

Answer 7

6.626 x 10^-34 J•s

Question 8

f

Answer 8

Frequency

Question 9

Kinetic energy formula

Answer 9

K=1/2mv^2

K=kinetic energy
M=mass
V=Velocity (m/s)

Question 10

Speed of light formula

Answer 10

V=f¥ (lambda)

Question 11

Speed of light (c)

Answer 11

3x10^8 m/s

Question 12

Angular momentum formula

Answer 12

L=nh/2pi

n=principal quantum number
h=plancks constant

Question 13

Energy of the electron

Answer 13

E=-RH/n2

E is directly proportional to n (hence the negative sign)

Question 14

Rydberg unit of energy

Answer 14

2.18x10^-18 J/electron

Question 15

As electron go from a lower energy level to a higher energy level, they ____

Answer 15

Absorb light, higher potential, excited, distant from nucleus

Question 16

Electromagnetic energy of photons formula

Answer 16

E=hc/wavelength (lambda)

Question 17

Energy transitions do not form a continuum but rather are quantized to certain frequencies. A _____________ (2) is where each line on the emission spectrum corresponds to a specific electron transition. Because each element can have its electrons excited to a different set of distinct energy levels each possess a unique ____________(3) which can be used as a fingerprint for the electron.

Answer 17

Line spectrum; atomic emission spectrum

Question 18

E=hf=hc/wavelength(lambda)

Energy is _______proportional to wavelength

Answer 18

Inversely

Question 19

E vs -E

Answer 19

Positive E= emission

Negative E= absorption

Question 20

E=hc/wavelength = _______

Answer 20

-RH[1/ni^2 - 1/nf^2]

Also—-

-E= -RH[1/ni^2 - 1/nf^2] AND 
E= -RH[1/ni^2 - 1/nf^2]

(Emission vs absorption)

Question 21

Delta E is the same for absorption and emission between any two energy levels according to the law of__________

Answer 21

Conservation of energy

Question 22

Heisenberg uncertainty principle

Answer 22

It is impossible to simultaneously determine, with perfect accuracy, the angular momentum and the position of an electron.

Question 23

Pauli exclusion principle

Answer 23

No two electrons in a given atom can possess the same set of four quantum numbers (n,l,ml,ms)

Question 24

Spectroscopic notation

Answer 24

Shorthand representation of the principal and azimuthal quantum number (ex:1s,6p,3d, etc.etc.)

Question 25

Maximum number of electrons within a subshell

Answer 25

4l + 2

Question 26

Maximum number of electrons within a shell

Answer 26

2n^2

Question 27

Aufbau Principle

Answer 27

Aka building Principle–electrons fill from lower to higher energy subshells and each subshell will fill completely before electrons begin to enter the next one

Question 28

The n+l rule

Answer 28

Used to rank subshells by increasing energy. The lower the sum of n+l, the lower the energy of the subshell. If two subshells possess the same n+l value, the subshell with the lower n has a lower energy and will fill with electrons first.

Question 29

Hunds Rule

Answer 29

Within a given subshell, orbitals are filled such that there are a maximum number of half filled orbitals with parallel spins. (Electrons prefer their own seat on the bus before doubling up with another electron)

Question 30

Paramagnetic

Answer 30

A magnetic field will cause parallel spins in unpaired electrons and therefore cause an attraction

Question 31

Diamagnetic

Answer 31

Materials consisting of atoms that have only paired electrons will be slightly repelled by a magnetic field and are said to be diamagnetic