3 Atomic Structure and the Periodic Table

Question 1

The sum of an atom is the sum of its

Answer 1

neutrons and protons.

Question 2

The atomic number is the same as the

Answer 2

number of protons.

Question 3

Quantum Numbers:

Shells: n=

Answer 3

1,2,3. . .

Question 4

Subshells: l =

Answer 4

0, 1, 2. . .

The angular momentum quantum number, or subshell, describes the shape of an electron’s orbital.

• The first shell (n=1) has one subshell s, or l = 0
• The 2nd shell (n=2) has two subshells: s (l=0), and p (l=1)
• The 3rd shell (n=3) has 3 subshells: s(l=0), p(l=1), d (l=2)

Question 5

Orbitals: m_l =

Answer 5

. . .-1, 0, 1. . .

m_l = +-L

Question 6

Spin: m_s =

Answer 6

+1/2, -1/2

Each orbital can contain two electrons: one with a positive spin and one with a negative spin.

Question 7

Diamagnetic elements have all of their electrons

Answer 7

spin paired. paramagnetism are not paired, and are more affected by magnetic fields.

Question 8

Energy of an electron:

E_n =

Answer 8

-2.178 X 10^-18 / N² Joules

E_n= the energy of the electrons

n = the principle quantum number of the electron

Question 9

(DELTA)E =

Answer 9

hv = hc / (lambda)

(Delta)E = energy change

h= plancks constant, 6.63 X 10^-34 Joules-sec

v = frequency of the radiation

lambda = wevelength of the radiation

c = the speed of light, 3.00 X 10⁸ m/sec (c = lambdaf)

Question 10

The de Broglie equation

lambda =

Answer 10

h/mv

lambda = wavelengh associated with a particle

m= mass of particle

v = speed of the particle

mv = p = momentum of the particle

h=planck’s constant, 6.63 X 10 ^-34 Joule-Sec

Question 11

Moving from left to right across the periodic table, atomic radius

Answer 11

decreases

Question 12

Moving down a group, atomic radius

Answer 12

increases.

Question 13

Cations(positively charged ions) are

Answer 13

smaller than atoms.

Question 14

Anions (negatively charged ions) are

Answer 14

larger than atoms

Question 15

Ionization energy

Answer 15

Energy required remove an electron from an atom

Question 16

Electronegativity

Answer 16

Electronegativity refers to how strongly a nucleus attracts electrons of other atoms.

Question 17

Moving from left to right across a period, ionization energy and electronegativity

Answer 17

increases.

Question 18

Moving down a group, ionization energy and electronegativity

Answer 18

decreases.