Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Inorganic - 6.1 - Shapes And Molecules > Flashcards

Inorganic - 6.1 - Shapes And Molecules Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Chemistry flashcards Periodic Table flashcards Chemistry 101 flashcards Organic Chemistry 101 flashcards
1
Q

Linear bonding

A
  • 180
  • 2/0
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Non - linear

A
  • 104.5
  • 2/2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Pyramidal

A
  • 107
  • 3/1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Trigonal planar

A
  • 120
    -3/0
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Tetrahedral

A
  • 109.5
  • 4/0
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Octahedral

A
  • 90
  • 6/0
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Examples of shapes

A
  • linear = CO2
  • nonlinear = H2O
  • trigonal planar = BF3
  • pyramidal = NH3
  • tetrahedral = CH4
  • octahedral = SF6
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How to make structure of poly atomic ions

A

Always start with double bonds and see where dative bonding could take place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Nitrate ion shape

A

Trigonal planar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Sulphate ion shape

A

Tetrahedral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Carbonate ion shape

A

Trigonal planar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Phosphate ion shape

A

Tetrahedral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Ammonium ion shape

A

Tetrahedral using DATIVE bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a dipole

A

The separation of charges between atoms due to differences in electronegativity causing polarity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do London forces work

A
  • all polar and non-polar molecules can have as the movement of electrons in the bonding chnages
  • this creates a temporary/ instantaneous dipole
  • due to its polarity and charge, it will induce a dipole on a neighbouring molecule
  • this process continues
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why are London forces weak

A

Due to their temporary nature, London forces do not last long and with a large magnitude

17
Q

How can London forces become stronger

A

The larger the number of electrons (nuclear charges), the stronger the forces induced, this will require a larger amount of energy to overcome and so results in a larger mp/bp

18
Q

What are permanent dipole-dipole interactions

A
  • only a polar molecule can have this
  • when a polar molecule like HCl is around another polar molecule, it will have a force of attraction
  • as it is stronger, it requires a larger amount of energy to overcome and so larger mp/bp
19
Q

What are simple molecules

A

E.g. H2O, CO2, H2, N2, O2

20
Q

Bonding in simple molecules

A

Simple molecules have weak intermolecular forces between molecules and strong covalent bonds between atoms

21
Q

Properties of simple molecules

A

Due to weak intermolecular, these are easily overcome with less energy and broken however when changing state only these change. The covalent bonds are much stronger and require a lot of energy to overcome and so usually do not break.

22
Q

How does non-polar dissolve in non- polar

A
  • the interactions weaken the intermolecular forces (LF) in both and the compound dissolves, forming the LF with each other, so that the energy is conserved
23
Q

Non polar with polar substances

A
  • the interactions once again break the LF in both, however the permanent dipole-dipole interactions in the polar solvent, are too strong to be broken and so will not allow for solute to dissolve and will not form bonds with each other, making it not conserved
24
Q

Polar with polar solvents

A

Both the LF and perm break and once again bonded tog so energy conserved however not always the case

25
Q

Electric conductivity

A
  • non-polar molecules do not have any free (delocalised) electrons and so will not be able to carry current and conduct
  • polar molecules will be able to conduct when molten or aqueous as the ions are free to move and so can conduct
26
Q

What is hydrogen bonding

A

Special type of permanent dipole dipole interaction between molecules:
- need electronegative elements - N,O, F
- need to have hydrogen bonded to them

27
Q

How does hydrogen bonding act

A

Between the hydrogen atom of a molecule and the lone pair of the electronegative atom

28
Q

How to draw hydrogen bonding

A

Must show:
- charges
- lone pair
- dashed line for bond
- linear bond of 180 deg

29
Q

Unusual properties of water

A
  • ice less dense: when ice is formed, the hydrogen bonds rearrange from liquid to solid. The lattice structure turns into an open tetrahedral shape and structure with many holes. These holes separate and distance the bonds, making them less dense. When ice melts, the lattice collapses and they move closer together
  • high mp/bp: water contains LF, perm and hydrogen bonding. These increase in van der waal’s requires a lot of energy to overcome and so significantly higher
  • High surface tension and viscous resulting in droplets and insects to walk on pond surfaces
30
Q

Hydrogen bonding in DNA

A

À and G - both have purine bases with two ringed structures
T and C - both pyrimidine bases with single ringed structures

31
Q

Bond enthalpy of all bonds

A

LF: 1-10
Perm: 3- 25
Hydrogen: 10-40
Covalent: 150-500

32
Q

When talking about shape of mol

A
  • eprt
  • bond angle
  • how many b/l
  • relate back to question
33
Q

What is electron pair repulsion theory

A
  • where electrons around central atom determine shape of mol or ion
  • due to the repulsion between bonded and lone pairs
  • this will change the shape depending on its strength to be arranged as far apart as possible to minimise repulsion
34
Q

Factors affecting electronegativity

A
  • number of shells (atomic radius) - if electrons are closer to the nucleus with less shells, it will have greater force of attraction
  • charge (number of protons) - more opposite charges will attract and pull of e is greater
35
Q

What is electronegativity

A

With any covalent bond, there is a force of attraction of nucleus of atom and shared pair of electrons. However, if following the factors, (small period number and high charge), there will be a greater efoa to pull electrons. This pull of attraction for the electrons is electronegativity. And what creates a small partial charge of a dipole

  • the ability for an atom to attract electrons in pair in a covalent bond
36
Q

Polymolecules can have…

A

Different number of shapes.

37
Q

Why are molecules polar?

A
  • Mention all dipoles evident
  • has/has no symmetrical structure
  • dipoles cancel/ reinforce each other
38
Q

How to determine mp/bp?

A
  • see all forces: covalent, intermolecular, ionic
  • see which can be increased - LF with e , perm with e and hydrogen with how many bond
  • see structure - if it is giant or repeating or just simple molecule

Chemistry (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions