test

Question 1

What are the uses of mass spectrometry?

Answer 1

-Identify unknown compounds
-Find relative abundance of each isotope of an elemnt
-Determine structural information

Question 2

How does a mass spectrometer work

Answer 2

-Sample is made into positive ions
-Passes through the apparatus and are separated according to mass to charge ratio
-Computer analyses the data and produces mass spectrum

Question 3

what is an empirical formula

Answer 3

Simplest whole number ratio of atoms of each element present in a compound

Question 4

orbital definition

Answer 4

a region of space around the nucleus where there is a high probability of finding an electron

Question 5

outline s orbitals

Answer 5

-can hold 2 electrons
-have spherical shape

Question 6

outline p orbitals

Answer 6

-can hold 2 electrons
-have dumbbell shape

Question 7

outline s sub shells

Answer 7

-made from 1 s-orbital
-can hold 2 electrons

Question 8

outline p subshels

Answer 8

-made from 3 p-orbitals
-can hold 6 electrons

Question 9

outline d-orbitals

Answer 9

-can hold 2 electrons
-shells 3 and 4 contain

Question 10

What is the Aufbau Principle

Answer 10

Fill in increasing order of energy

Question 11

What is the Pauli Exclusion Principle

Answer 11

Electrons pair with opposite sound to stabilise the atom

Question 12

What is Hund’s Rule

Answer 12

One electron occupies each orbital before pairing up

Question 13

What produces a giant ionic lattice

Answer 13

Electrostatic attraction between the positive and negative ions

Question 14

What is a giant ionic lattice

Answer 14

Generally crystals with straight edges, suggesting ions line up alternatively in repeating straight line.

Question 15

Why is the melting point of ionic lattices so great?

Answer 15

A lot of energy is required to break the bonds so the ions can move apart and change state

Question 16

What can increase melting and boiling points

Answer 16

As charge of the ions increase.

Question 17

Outline the solubility or ionic lattices

Answer 17

-Relative strengths of the attractions within the lattice and between the ions and water molecules determine solubility
-An ionic compound where ions have large charges the ionic attraction may be too strong for water to break lattice stricter

Question 18

What is a dative covalent bond

Answer 18

Both bonding electrons originate from the same atom

Question 19

Isoelectronic species

Answer 19

Have the same electron configuration

Question 20

Covalent molecule

Answer 20

Shared pair of electrons between atoms with strong electrostatic attraction between the shared pair of electrons and the nuclei of the bonded atoms

Question 21

Lone pair

Answer 21

pair of electrons not involved in bonding

Question 22

Trigonal planar

Answer 22

-3 Bond pairs
-120°

Question 23

Linear

Answer 23

-2 bond pairs
-180°

Question 24

Tetrahedral

Answer 24

-109.5°
-4 bond pairs

Question 25

octahedral

Answer 25

-6 bond pairs
-90°

Question 26

Trigonal Pyramidal

Answer 26

-5 bond pairs
-90°
-120°

Question 27

Electron pair repulsion theory

Answer 27

Electrons exists in pairs in spaces we refer to as orbitals
They are all negatively charged so will repel other pairs if they get too close
Therefore electrons will take up positions as far away from each other as possible to minimise repulsion.

Question 28

Lone pair rule for molecule shapes

Answer 28

-Lone pair + lone pair repulsion is greater than lone pair + bond pair repulsion which is greater than bond pair + bond pair repulsion

Question 29

NH3 molecule shape

Answer 29

-trigonal pyramidal
-107°

Question 30

H20 molecule shape

Answer 30

-non-linear
-104.5°