SC5,SC6 & SC7 Flashcards

(59 cards)

1
Q

What are bonds?

A

Bonds are forces of attraction that holds atoms together

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

What happens when bonds form between atoms?

A

Energy is released from the atoms which makes them more stable (less reactive)

More stable with a full outer shell

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

How are ions formed?

A

It’s the transfer of electrons between atoms which form charged particles (ions)

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

What is ionic bonding?

A

Metal and non metal

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

What happens when metals react?

A

They lose outer shell elections to leave a full electron shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens when non-metals react?

A

They gain electrons to achieve a full electron shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are cations?

A

When metals lose electrons to form positive ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are anions?

A

When non-metals gain electrons to form negative ions

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

What are electrostatic forces?

A

The force of attraction between all positively and negatively charged objects

Hold oppositely charge ions together and form an ionic bond between them

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

How many electrons are lost or gained in group 1 elements?

What is the charge on the ion?

A

1 electron is lost

1+

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

How many electrons are lost or gained in group 2 elements?

What is the charge on the ion?

A

2 electrons are lost

2+

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

How many electrons are lost or gained in group 6 elements?

What is the charge on the ion?

A

2 electrons are gained

2-

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

How many electrons are lost or gained in group 7 elements?

What is the charge on the ion?

A

1 electron is gained

1-

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

What are ionic compounds?

A

They’re formed by the loss and gain of electrons

Held together by strong electrostatic forces of attraction between oppositely charged ions

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

What is a lattice structure?

A

The strong bonds allow ‘billions’ of ions that are packed together in a regular repeating arrangement called a lattice structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the formula of ionic compounds?

A

Needs to contain the same number of positive charges as negative charges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the melting and boiling points like in ionic compounds?

A

The forces are strong
A lot of energy needed to overcome forces
Need to be heated on high temperatures before they change state
High melting and boiling points

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What happens if an ion has more than 1 charge?

A

They attract other ions more strongly than ions with 1 charge
More energy needed to overcome electrostatic forces of attraction
Melting points = higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

When do ionic compounds conduct electricity?

A

When they are molten or dissolved in water

Not when they are solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the conditions for a substance to conduct electricity?

A

Must contain charged particles (carry the current)

Particles must be free to move

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where are the negative ions (anions) attracted to?

A

They’re attracted to the positive electrode, called the anode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where are the positive ions (cations) attracted to?

A

They’re attracted to the negative electrode, called the cathode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Do the ions or electrons move to conduct electricity?

A

The ions moving enable ionic compounds to conduct electricity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are molecular substances?

A

Contain groups of atoms that are held together by strong bonds called covalent bonds

25
What is a covalent bond? | When are covalent bonds formed?
A covalent bond is a shared pair of electrons When non-metals react together Produced by sharing pairs of electrons
26
What happens when the bond forms?
It makes the atom more stable as they use the shared electrons to complete their outer shell E.g noble gases
27
What are the forces of attraction like in the bonded atom?
Strong electrostatic forces between the positive nuclei and negative electrons Weak forces between molecules (intermolecular forces), doesn’t take much energy to overcome the weak intermolecular forces
28
What are compounds?
Compounds contain atoms of more than one element, chemically joined together by bonds
29
What is the conduction of electricity like in molecules?
They can’t conduct electricity as the electrons are free to move as there are strong electrostatic forces that hold the negatively charged electrons and positive nucleus together
30
What is a polymer?
A polymer is formed when monomers (small,simple molecules) are joined in a chain
31
What do most polymers contain?
Contain a chain of carbon atoms
32
What are the features of longer polymers?
More intermolecular forces between them | Have higher melting and boiling points than shorter ones
33
What are allotropes?
Different forms of the same element
34
What are fullerenes?
Simple molecules formed by carbon in which each carbon atom is covalently bonded to 3 other carbon atoms
35
What are the features of fullerenes?
They have weak intermolecular forces between molecules Low melting point and boiling point Soft and slippery Molecules strong due to covalent bonds
36
What is graphene?
Not a simple molecule Consists of sheets of carbon atoms with no fixed formula Light (one atom thick) but covalent bonds make it very strong
37
Is graphene a good electrical conductor?
Yes it is because it’s electrons are free to move to across the surface
38
Name to allotropes of carbon that aren’t simple structures?
Diamond and graphite (covalent, giant molecular structures)
39
What is the melting point in diamond and graphite?
The melting point is high as it has strong covalent bonds that need lots of energy to be broken
40
How many covalent bonds does graphite have?
3 covalent bonds for each atom | Gives a layered structure so not all electrons are held together in covalent bonds
41
What are delocalised electrons?
Electrons that are free to move and can carry an electrical current Graphite is a good conductor (and cheap and not reactive)
42
Why is graphite soft?
Held together by weak forces of attraction which allow layers to slide past each other
43
How many covalent bonds does diamond have?
Held together by 4 covalent bonds
44
What is the structure like in diamond?
Rigid network of carbon atoms in a tetrahedral arrangement, held together by strong covalent bonds
45
What is diamond useful for?
Tools
46
Is diamond an electrical insulator?
Yes it is because it has no free charged particles
47
What happens to the lecterns in the outer shell of metal atoms?
Lost from each atom and become free to move randomly throughout the metal
48
What happens once the outer electrons are lost from the metal atom?
They form a giant lattice of positive metal ions surrounded by a sea of delocalised electrons
49
What is metallic bonding?
Electrostatic attraction between the positive ions and the negative delocalised electrons Attraction is strong so metals have high boiling and melting points
50
Why are metals malleable?
The layers of ions slide over each other when the metal is hit Sea of electrons holds ions together so metal changes shape
51
How do metals conduct electricity?
Delocalised electrons move randomly between positive metals in all directions When voltage applied, electrons move to positive side so transfers energy and forms an electrical current
52
Why do some substances conduct electricity better than others?
The electrical conductivity of metals increases as the number of delocalised electrons increases
53
Which has a higher electrical conductivity: magnesium or sodium?
Magnesium as it has a 2+ charge so contributes 2 electrons to the sea of electrons whereas sodium has a 1+ charge so only contributes 1 electron to the sea of electrons Magnesium has better electrical conductivity than sodium
54
What are simple molecules?
Non metal elements and compounds
55
What are the properties of simple molecules?
Low melting/boiling points Few soluble in water Most don’t conduct electricity
56
What are the bonds like between giant covalent?
Covalent bonds formed when atoms share pairs of electrons
57
What are the properties of giant covalent structures?
High melting/boiling points Insoluble in water Most don’t conduct electricity (carbon as graphite does)
58
What is the structure of metallics?
Billions of ions held together in a giant lattice structure of positive ions in a sea of negative delocalised electrons
59
What is the properties of metallics?
High melting/boiling points Insoluble in water Conduct electricity when solid or liquid