Atomic Structure

Question 1

What is the symbol proton number?

Answer 1

Z

Question 2

What is the symbol for the atomic mass?

Answer 2

A

Question 3

What did J.J Thomson think an atom was?

Answer 3

He discovered that atoms were divisible and that electrons (which were smaller and lighter) were imbedded inside a positively charged sphere (plum pudding model)

Question 4

What did Ernest Rutherford discover?

Answer 4

He fired alpha partials at a thin film of gold and instead of bouncing off, most particals passed through. This lead to the idea that an atom was mostly empty space with a positive nucleus and orbiting electrons

Question 5

What must electrons do when moving between orbits?

Answer 5

They must emit or absorb electromagnetic radiation of a particular frequency

Question 6

What is the atomic mass?

Answer 6

1/12 of the mass of a single carbon-12 atom

Question 7

What is the mass and charge of a proton?

Answer 7

Mass = 1.0073amu
Charge = +1

Question 8

What is the mass and charge of a neutron?

Answer 8

Mass = 1.0087amu
Charge = no charge

Question 9

What is the mass and charge of an electron?

Answer 9

Mass = 0.00055amu
Charge = -1

Question 10

What does the nucleus contain and what is its charge?

Answer 10

Protons and neutrons
Positive charge

Question 11

What are electron shells split into?

Answer 11

Sub-shells which have slightly different energies

Question 12

What do sub-shells split into?

Answer 12

Orbitals

Question 13

What is the mass number of an atom?

Answer 13

Protons + Neutrons

Question 14

What are positive ions called?

Answer 14

Cations

Question 15

What are positive ions?

Answer 15

Atoms which have lost an electron

Question 16

What are cations attracted to?

Answer 16

The cathode and anything negativity charged

Question 17

What are negative ions called?

Answer 17

Anions

Question 18

What are negative ions?

Answer 18

Atoms which have gained electrons

Question 19

How do you calculate the charge of an ion?

Answer 19

Charge = number of protons - number of electrons

Question 20

What will the overall charge of any chemical substance and why?

Answer 20

0 because cations will always be accompanied by anions in solid or in solution

Question 21

What is the theory of electroneutrality?

Answer 21

That cations will always be accompanied by anions

Question 22

What are isotopes?

Answer 22

Atoms of the same element that have the same number of protons but a different number of neutrons

Question 23

What effects do isotopes have on the elements chemistry?

Answer 23

Since neutrons have no electric charge and chemistry is largely about electrostatic interactions, the change in mass rarely effects it’s chemistry

Question 24

What are the steps in mass spectrometry ?

Answer 24

1. Ionisation
2. Acceleration
3. Deflection
4. Detection

Question 25

What happens in stage 1 of mass spectrometry?

Answer 25

The sample is vaporised and then passes into an ionising chamber where they are hit with a beam of electrons to form positively charged ions

Question 26

What happens in stage 2 of mass spectrometry?

Answer 26

An positive electric field is applied to the chamber and the ions repel them and shoot towards 3 negatively charged slits

Question 27

What happens in stage 3 of mass spectrometry?

Question 28

What happens in stage 4 of mass spectrometry?

Question 29

What can happen during the ionisation stage of mass spectrometry when using electron impact?

Answer 29

The sample could fragment

Question 30

What is the equation for kinetic energy?

Answer 30

Kinetic energy = 1/2 x mass x velocity2

Question 31

What is the time of flight calculation?

Answer 31

Time = distance / (square root (2 x kinetic energy) / mass)

Question 32

What type of ion travels faster in mass spectrometry?

Answer 32

The lighter ions

Question 33

What charge does the detection plate have in mass spectrometry?

Answer 33

Negative charge

Question 34

How do you calculate the relative atomic mass ?

Answer 34

( isotope abundance x mass isotope mass number ) + ( isotope abundance x mass isotope mass number )

Question 35

How many electrons can orbitals contain?

Answer 35

They can hold a maximum of 2 electrons

Question 36

What do physical properties of N element depend on?

Answer 36

The mass of the atom

Question 37

What do chemical properties of an element depend on?

Answer 37

The number and arrangement of electrons