CH3Arrangement of electrons in the atom

Question 1

Outline bohrs atomic theory based on the hydrogen emission spectrum.

Answer 1

1. Electrons are restricted to energy levels where they have a quantised energy.
2. Electrons occupy the ground state.
3. If a fixed amount of energy is absorbed, the electron can jump to a higher energy level.
4. Electrons fall back down to a lower energy level and emit photons of light at a specific frequency.
5. Each element has different distributions of energy levels, which give rise to different electronic transitions, and unique emission / absorption spectra

Question 2

What colour do the following metals give off in the flame test?
1. lithium
2. potassium
3. barium
4. strontium
5. copper
6. sodium

Answer 2

1. crimson
2. lilac
3. green
4. red
5. green blue
   6.

Question 3

Energy level

Answer 3

The fixed energy value that an electron in an atom may have

Question 4

Ground state

Answer 4

Of an atom is one in which the electrons occupy the lowest available energy level

Question 5

Excited state

Answer 5

Of an atom, is one in which the electrons occupy higher energy levels than those available in the ground state.

Question 6

e2-e1=hf

Answer 6

E2= energy of higher energy level
E1- Energy of lower energy level
h=plancks constant
f= frequqncy of light

Question 7

Atomic orbital

Answer 7

A region in space within which there is a high possibility of finding an electron (95%).

Question 8

Balmer series

Answer 8

Electron transitions are from higher energy levels to n=2
give rise to lines in the visible spectrum

Question 9

Lyman series

Answer 9

Electron transitions are from hgher energy levels to n = 1
give rise to lines in the ultraviolet region of the spectrum

Question 10

Patschen series

Answer 10

Electron transition are from higher energy levels to n=3
give rise to lines in the infrared region of the spectrum.

Question 11

Sublevel

Answer 11

A subdivision of a main energy level, and consists of one or more orbitals of the same energy.

Question 12

Heisenbergs uncertainty Principle

Answer 12

It is impossible to measure at the same time both the position and velocity of an electron

Question 13

Limitations of Bohrs Theory

Answer 13

-Worked for hydrogen, but not for atoms with more electrons

-Wave- Particle duality

-Heisenberg’s Uncertainty Principle

-Sublevels

Question 14

Who was Erwin Schrotwoosdinger

Answer 14

Devised mathematical equations to work out the probability of finding an electron in any particular sublevel in any atom.
Gave us the shapes of the four types of robitals

Question 15

Four types of orbitals

Answer 15

SPDF

Question 16

S orbitals

Answer 16

-spherical - the probability of finding an electron is identical in all directions from the nucleus

• Differ in size

Question 17

P orbitals

Answer 17

• dumb-bell shaped
• Each p sublevel consists of three parts px, py and pz
  -these orbitals differ in orientation in space
• The orbitals are at 90 degree right angles to each other

Question 18

Louis de Broglie

Answer 18

Suggested all moving particles had a wave motion associated to them.

Question 19

Wave- particle duality

Answer 19

The concept that electrons behave like waves and like particles.

Question 20

Reasoning for heisenbergs uncertainty principle

Answer 20

If a beam of light is used to detect an electron, the beam strikes the electron, immediately changing its velocity as it has such a small mass.

Question 21

Why was ernest rutherfords proposal too simple

Answer 21

He proposed electrons revolved around the nucleus, however , the eletrons would spiral into the nucleus and atom would collapse.

Question 22

Spectrometer vs spectroscope

Answer 22

Both are used to observe spectra however
Spectrometer can measure wavelengths of light.

Question 23

Emssion spectrum appearance

Answer 23

Coloured lines on a dark background

Question 24

Absorption spectrum appearance

Answer 24

Dark lines on a coloured backgroundses

Question 25

Uses for aas

Answer 25

• water analysis Pb Hg Cd
• blood analysis Pb
• forensics -> gunshot residue Pb Sb Ba

Question 26

What is atomic absorption spectrometry

Answer 26

Analytical technique used to measure the concentration of elements.

Question 27

What were bohrs observations and explained

Answer 27

-Elements emit only certain frequencies of light
-Bohr suggests that the electrons in atoms can only have a fixed amount or quantised energy

Question 28

Flame test use

Answer 28

Used to identify metals present in unknown compounds