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Flashcards in Atomic structure Deck (50):
0

Relative mass of electron

1/1840

1

Strong nuclear force

Holds protons and neutrons together

2

Electrostatic force

Hold electrons and protons together

3

Number of electrons in each shell

2n^2

4

Atomic number (Z)

Number of protons

5

Mass number (A)

Number of protons + neutrons

6

Isotope

Same number of protons but different number of neutrons

7

Order of sub-levels

s, p, d, f

8

s-sub shell

Hold up to 2 electrons

9

p-sub shell

Hold up to 6 electrons

10

d-sub shell

Hold up to 10 electrons

11

f-sub shell

Hold up to 14 electrons

12

Order of sub shells

1s, 2s, 2p, 3s, 3p, 4s, 3d, 5s, 4d, 5p

13

Ionisation energy

The energy requires to remove one mole of electron from one mole of a gaseous atom

14

Jump in successive ionisation energies

Tells the number of electrons in each main level

15

Mass spectrometer

Identify different isotopes
Determine relative atomic masses & relative molecular masses
Under vacuum condition + gaseous sample

16

Mass spectrometer
Ionisation

A beam of electron from ELECTRON GUN removes electrons from atoms of the sample > positive ions

17

Mass spectrometer
Acceleration

Positive ions attracted towards negatively charged plates.
Speed depends on their mass.
Forms the ions into a beam

18

Mass spectrometer
Deflection

magnetic field deflects the beam of ions (depends on ratio m/z and magnetic field strength)

19

Mass spectrometer
Detection

Detector accept electrons > lose energy > create current (proportional to the ABUNDANCE off each ion)

20

Relative atomic mass

The ratio of the average mass of an atom of an element to 1/12th the mass of an atom of carbon-12

21

Avogrado constant

6.022 x 10^23
Number of atoms in 12g of carbon-12

22

Idea gas equation

P(Pa) V(m^3) = n R T(K)

23

Mole equation

Mass = mole x atomic no,Z

24

Concentration

Mole = M(mol dm-3) V(dm3)

25

Atom economy

Mass of desired product /
total mass of reactant x 100

26

Percentage yield

Actual / theory x 100

27

Ionic bond

A transfer of electron from metals to non-metals

28

Properties of ionically bonded compound

Brittle - the force may move the ions and produce repulsive force as they form a lattice of alternating + and - ions
Conduct electricity when molten or in solution

29

Covalent bond

Is sharing a pair of electrons btw non-metals

30

Co-ordinate bond

Covalent bond btw 2 atoms where one of the atoms provide both electrons that form the bond

31

Co-ordinate bond
Electron deficient

Atom that accepts electron pair
Doesn't have full outtershell

32

Co-ordinate bond
Donating atom

The atom donating the electrons
Has a pair of unused electrons or lone pairs

33

Electronegativity

The power of an atom to attract the electron density in covalent bond

34

Electronegativity depends on

1.effective nuclear charge (no of protons)
2.atomic radius
3.shielding

35

Polarity

Unequal sharing of electrons btw atoms in covalent bond

36

Properties of simple covalently bonded compound

Low mp/bp - weak intermolecular force btw molecules
Dissolve in water
Doesn't conduct electricity

37

Metallic bond

Merging of outer main level electrons forming a lattice of positive ions existing in the sea of delocalised electrons

38

Metallic bind strength depends on

1.effective nuclear charge(no of protons)
2.size of ion (smaller=electrons closer)

39

Properties of metals

Malleable and ductile - still in the same environment
Conduct electricity - free electrons in sea of delocalised electron to carry charge
High mp/bp - strong attraction btw giant structure

40

van der Waals

Instantaneous dipole-induced
Distribution of charge is changing at every instant

41

Dipole-dipole forces

Btw molecules with permanent dipole (polarity)

42

Hydrogen bond

Bond btw hydrogen and O N or F (very electronegative atoms)

43

2 centre of charges

Linear shape
180

44

3 centre of charges

Trigonal plannar
120

45

4 centre of charges

Tetrahedral
109.5

46

5 centre of charges

Trigonal bipyramid
120 and 90

47

6 centre of charges

Octahedral
90

48

5 centre of charges
4electron + lone pair

Triangular pyramid
107.5

49

4 centre of charges
2electrons + 2lone pairs

V-shape
104.5