3 Atomic structure and the periodic table

Question 0

What is the aufbau principle?

Answer 0

1s(2) 2s(2) 2p(6) 3s(2) 3p(6) 4s(2) 3d(10) 4p(6)

Question 1

What is the first ionisation energy?

Answer 1

The energy required to remove one mole of electrons from one mole of gaseous atoms to form one mole of gaseous positive ions

Question 2

How do you write noble gas configuration?

Answer 2

You write the noble gas in square brackets then everything after that electron configuration afterwards

Question 3

What are the anomalies in the electron configuration?

Answer 3

Chromium
Copper
(Both begin with C)

Question 4

What is the electron configuration of copper? Why is it different?

Answer 4

[Ar] 4s(1) 3d(10)

It is more stable to have one full shell and one half full shell

Question 5

What is the electron configuration for chromium and why is it different?

Answer 5

[Ar] 4s(1) 3d(5)

It is more stable to have two half shells

Question 6

What do you have to write before the electron configuration of ions?

Answer 6

The symbol and the charge

Question 7

What orbital must you remove electrons from first when writing the electron configuration for any ion?

Answer 7

4s

Question 8

Describe Thompson’s plum pudding model of the atom

Answer 8

Negative electrons embedded in a sphere of positive charge

Question 9

What was the experiment performed by Rutherford and his colleagues which led to the proposal of the nuclear atom?

Answer 9

They directed abeam out alpha particles at a thin metal foil

Question 10

What did Rutherford observe that led to his proposal of atoms are mostly empty space with most of them are centred in a very small and nucleus?

Answer 10

Most alpha past pools pass straight through detected on the other side.. Somewhere deflected

Question 11

It is the ratio of the diameter of the nucleus to the diameter of the atom?

Answer 11

1:10000

Question 12

What was the experiment that Bohr studied that led to the concept of quantum shells?

Answer 12

A gas is heated or an electrical charge is passed through it. It gives out light which can be passed through the prism or diffraction grating that splits up to form spectrum

Question 13

What is the series of lines produced by Bohrs experiment called?

Answer 13

Find spectrum or emission spectrum which is made up of a series of separate lines or bands

Question 14

Explain the observations in Bohr’s experiment in terms of electrons and energy levels

Answer 14

Electrons are arranged in a shell around the positive nucleus. As you move away from the centre energy levels become closer together as they do in the line spectrum. Light is emitted when excited electrons fall back to the ground level

Question 15

What could Bohr’s equations allows scientists to calculate?

Answer 15

Radius of hydrogen atom
It’s energy levels
It’s ionisation energy

Question 16

What was the main problem for faced with his equations?

Answer 16

The behaviour of atoms with more than one electron

Question 17

What property of light is the energy of light related to?

Answer 17

Frequency of light

Question 18

The emission spectra only consists of a limited number of frequencies. What does this tell us about the atom?

Answer 18

Only a limited number of energy changes or transitions can take place within the atom

Question 19

What does quantum mechanics say about the arrangement of electrons and atoms?

Answer 19

Arranged in a series of shells
Each shell described by the principal quantum numbers
Each shell may contain a number of subshells

Question 20

What does the principal quantum number tell you about?

Answer 20

The size of the shell

Question 21

What is ionisation?

Answer 21

The complete removal of an electron from an atom

Question 22

Why is ionisation an endothermic process?

Answer 22

What must be done on an electron in order to overcome the attractive forces between it and the nucleus

Question 23

How are ionisation energy is measured?

Answer 23

Gradually increasing the voltage applied to a gas until it conducts electricity and emits light

Question 24

What does it mean when we say an atom is in its ground state?

Answer 24

It is at its lowest energy level

Question 25

What are the units for ionisation energies?

Answer 25

kJmol(-1)

Question 26

What is the first ionisation energy a measure of?

Answer 26

How tightly the outer electron is attracted to the positive nucleus

Question 27

Will not with a lower first ionisation energy be more or less reactive than one with the higher first ionisation energy?

Answer 27

More

Question 28

How do you calculate the energy needed to go from the magnesium atom to a magnesium 2+ ion?

Answer 28

The amount of energy needed to remove the first electron to the amount needed to remove the second

Question 29

What is an orbital?

Answer 29

The region where the electrons are most likely to be found

Question 30

How do you calculate the number of subshells?

Answer 30

Number of shell

Question 31

How do you calculate the number of orbitals?

Answer 31

Number of shells squared

Question 32

Two electrons in an orbital must have the same/different spin

Answer 32

Different

Question 33

Why are each of the P orbitals filled with one electron before pairing electrons up?

Answer 33

Electrons repel each other and they spread out to maximise the number unpaired electrons

Question 34

Why is the for 4s orbital fields before 3d?

Answer 34

It is at a lower energy level

Question 35

Why are inner electrons is not involved in chemical bonding?

Answer 35

They are strongly attracted to the nucleus

Question 36

The model of the behaviour of electrons wideness accepted by scientists consider electrons as waves/particles

Answer 36

Waves

Question 37

What is an electron cloud?

Answer 37

Electrons spread out around the nucleus

Question 38

What do maps of the electron density of electron clouds show us?

Answer 38

The shapes of the areas in spaceworthy electron is likely to be

Question 39

What happens to the size of the orbitals as principal quantum number increases?

Answer 39

The size of the P and S orbitals increase

Question 40

Can you draw the shapes of the orbitals?

Answer 40

Go look it up yourself

Question 41

What determines the blocks that the periodic table is split up into?

Answer 41

Which electron orbitals being filled

Question 42

Which groups make up the S block elements?

Answer 42

1 and 2

Question 43

Why are groups one and two known as the s block elements elements?

Answer 43

The outermost electrons are in the S subshells

Question 44

Give 4 properties of the S block elements

Answer 44

Very reactive Low melting and boiling point Low densities Conduct electricity

Question 45

Why are hydrogen and helium not considered part of the S block elements even though they have their outer electrons in the S orbitals?

Answer 45

They have different properties to the other elements

Question 46

What are the d block elements often referred to as?

Answer 46

The transition metals

Question 47

Why are the transition metals much less reactive than the S block elements?

Answer 47

In a D orbitals are being filled while the outer S subshell is full

Question 48

Give three properties of the D block elements

Answer 48

Conducts heat and electricity Hard and shiny Malleable

Question 49

What are the elements in the top row of the F block elements called?

Answer 49

Lanthanides

Question 50

What are the elements in the second row of the F block elements called?

Answer 50

Actinides

Question 51

Which are radioactive? The actinides or the lanthanides

Answer 51

Actinides

Question 52

Elements are contained within the P block?

Answer 52

All the nonmetals apart from hydrogen and helium and metalloids as well as some metals

Question 53

Give two properties of the pibroch metals

Answer 53

Conduct heat and electricity | Post-transition metals are relatively unreactive

Question 54

Which important property of metals do the metalloids have?

Answer 54

Conduct electricity

Question 55

What type of bonds do non-metals form with non-metals?

Answer 55

Covalent

Question 56

What type of bonds do non-metals form with metals?

Answer 56

Ionic

Question 57

What are the repeating patterns in the periodic table known as?

Answer 57

Periodicity

Question 58

What are the repeating properties of the elements in the periodic table know as?

Answer 58

Periodic properties

Question 59

Why does atomic radius decrease across a period?

Answer 59

The electrons in the outer shell of pulled closer to the nucleus due to an increase nuclear charge

Question 60

Why does atomic radius increases as you go down a group?

Answer 60

Electrons are not held so tightly because the force of attraction is shielded by other electrons They are further away

Question 61

Why do positive ions have a smaller radius than the ions from which they are formed?

Answer 61

The remaining electrons each have a greater share of the positive charge so more tightly bound Usually when an ion is formed a whole electron shell is lost

Question 62

Why do negative ions have a larger radius than the atom from which they are formed?

Answer 62

The addition of extra negative charge means that the electrons are less tightly bound to the nucleus

Question 63

What is the first ionisation energy of an element directly related to?

Answer 63

Attraction of the new class for the most loosely bound of the outer electrons

Question 64

What are the three main factors that affect the ionisation energy of an atom?

Answer 64

Attraction between nucleus and outermost electron Size of positive nuclear charge In the shells of electrons repelling other electrons or shielding the force of attraction

Question 65

Why does ionisation energy increase across a period?

Answer 65

Increasing positive nuclear charge across the period without the addition of any extra shells to shield outer electrons

Question 66

What is the evidence for sub shells?

Answer 66

The first ionisation energies of the elements do not increase smoothly across a period

Question 67

Why does ionisation energy decrease down a group?

Answer 67

Electrons become further away and the force of attraction is shielded by inner electrons which means that less energy is required to remove electrons

Question 68

What is the melting temperature of an element affected by?

Answer 68

The packing and the bonding of atoms in a substance

Question 69

Why do lithium, magnesium and aluminium have relatively high melting temperatures?

Answer 69

It takes a lot of energy to separate atoms as they are held tightly in a sea of electrons

Question 70

Why do carbon and silicon have such high melting temperatures?

Answer 70

Held together with ionic bonds in giant lattices

Question 71

Why do you nitrogen, oxygen and fluorine have low melting temperatures?

Answer 71

There are strong covalent bonds within the molecules however the molecules only held together by weak–molecular forces