Unit 1 - Inorganic Chemistry

Question 0

What is wavelength?

Answer 0

Wavelength is the distance between adjacent crests or troughs of a wave.

Question 1

What is the electromagnetic spectrum?

Answer 1

This is the range of frequencies or wavelengths of electromagnetic radiation.

Question 2

What is wavenumber?

Answer 2

Wavenumber is the reciprocal of wavelength and has units of cm^-1 (number of cycles per centimetre).

Question 3

What is frequency?

Answer 3

Frequency is the number of wavelengths that pass a fixed point in one second. The units are Hertz (Hz).

Question 4

What is the speed of light?

Answer 4

3x10^8m/s

Question 5

What is the excited state?

Answer 5

This is when an electron absorbs energy and moves to a higher energy level.

Question 6

What is the ground state?

Answer 6

The ground state is the lowest (energy) possible electronic configuration that the electrons in an atom can adopt.

Question 7

What is Heisenberg’s uncertainty principle?

Answer 7

Heisenberg’s uncertainty principle states that it is impossible to know precisely the position and angular momentum of an electron at one particular instance in time.

Question 8

What is the Pauli exclusion principle?

Answer 8

The quantum mechanical principle that states that two identical fermions cannot exist in the same quantum state simultaneously. (They must have different quantum numbers)

Question 9

Define Degenerate

Answer 9

Of equal energy.

Question 10

What is the Aufbau principle?

Answer 10

This principle states that orbitals are filled in order of increasing energy. (In terms of energy: s

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Question 11

What is Hunds Rule of Maximum Multiplicity?

Answer 11

Electron filling looks to maximise the number of parallel spins. (when degenerate orbitals are available, electrons fill each of them singly, keeping the spins parallel before pairing starts).

Question 12

What is spectroscopic notation?

Answer 12

This is the longer version of the condensed electronic configurations. This gives electronic configurations in terms of their respective orbitals.

Question 13

What is atomic emission spectroscopy used for?

Answer 13

Atomic emission spectroscopy is used to identify the elements contained within a given sample.

Question 14

What is atomic absorption spectroscopy used for?

Answer 14

Atomic absorption spectroscopy is used to determine the concentration of a particular metal element in a given sample.

Question 15

Describe the technique of atomic emission spectroscopy.

Answer 15

The sample is vaporised into the gas phase and excited by either a flame or electricity.The electrons in the gas sample drop back down to the ground state and release energy in the form of light (photons).The frequency and intensity of the resulting light can be used to determine the elements present in the sample. This works as distinct elements have characteristic energy values for their transitions from the excited state to the ground state.

Question 16

Describe the technique of atomic absorption spectroscopy.

Answer 16

The electrons in the sample I promoted to higher energy levels by absorbing energy. The wavelength of the absorbed energy can be used to determine which elements are present in the sample. The intensity of the absorbed light can be used to determine the concentration of these elements.

Question 17

What is a complex ion?

Answer 17

A central metal ion surrounded by ligands.

Question 18

What is a ligand?

Answer 18

A ligand is a negative ion or uncharged molecule with one or more lone pair of electrons.

Question 19

What is the spectrochemical series?

Answer 19

The spectrochemical series is a list of ligands in order of the size of the crystal field splitting caused in the d-orbitals.

Question 20

State the Spectrochemical Series.

Answer 20

Cyanide > Ammonia > Water > Hydroxide > Fluorine > Chlorine > Bromine > Iodine

Question 21

What is a dative covalent bond?

Answer 21

This is when one atom provides both of the electrons that form the bond.

Question 22

What is the co-ordination number?

Answer 22

This is the number of nearest neighbours by which an atom or ion is surrounded in a structure.

Question 23

What is a bidentate ligand?

Answer 23

A ligand that contains two atoms with lone pairs of electrons capable of bonding to a metal ion.

Question 24

What are coordination compounds?

Answer 24

These are compounds in which a central metal ion is attached to a group of surrounding molecules or ions by dative covalent bonds (otherwise known as coordinate bonds).

Question 25

What is a molecular orbital?

Answer 25

A molecular orbital is a region in space between the nuclei where there is a high probability of finding electrons. It is formed by the overlap of atomic orbitals.

Question 26

What is a Hexadentate ligand?

Answer 26

This is a ligand that bonds to a metal ion using electron pairs on six donor atoms.

Question 27

What is a monodentate ligand?

Answer 27

This is a ligand that bonds to a metal ion using the electron pair of a single donor atom.

Question 28

What is oxidation?

Answer 28

Oxidation is the loss of electrons from a substance. It can also be described as an increase in oxidation number.

Question 29

What is the “oxidation number”?

Answer 29

This is the formal charge assigned to each atom in a compound according to certain rules.

Question 30

What is reduction?

Answer 30

This is the gain of electrons by a substance. It can also be described as a decrease in oxidation number.

Question 31

What is Planck’s constant?

Answer 31

6.63x10^-34Js