Chemical Bonding Flashcards Preview

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Flashcards in Chemical Bonding Deck (65):
1

what is chemical bonding?

attraction between atoms involving electron transfer/sharing to form new compounds

2

what is a grouped ion?

more than one atom involved in the ion

3

what is the symbol for carbonate and its charge?

symbol = CO3 

charge = 2-

4

what is the symbol for ammonium and its charge?

symbol = NH4

charge = 1+ 

5

what is the symbol and charge for hydroxide?

symbol = OH

charge = 1-

6

what is the symbol and charge for nitrate? 

symbol = NO3

charge = 1-

7

what is the symbol and charge for sulfate?

symbol = SO4 

charge = 2-

8

what is the symbol and charge for phosphate? 

symbol = PO4

charge = 3-

9

what is valency?

the number of electrons an atom needs to complete the outer shell

those electrons are either gained or lost

10

do non-metals gain or lose electrons?

gain

11

what is an ion

a charged particle (positive or negative)

12

how does the cross rule work?

13

are metals negatively or positively charged and why?

positively charged (cations)

they lose electrons

14

are non-metals negatively or positively charged and why?

negatibely charged (anions)

they gain electrons

15

in the centre of the atom are two sub-atomic particles

these particles are the ...... and the .....

the ..... are positively charges

the ......have no charge and are .....

in the centre of the atom are two sub-atomic particles

these particles are the protons and the neutrons

the protons are positively charged

the neutrons have no charge and are neutral

16

the centre of an atom is ..... charged

the centre of an atom is positively charged

17

around the centre of the atom are negatively charges sub-atomic particles called .....

around the centre of the atom are negatively charges sub-atomic particles called electrons

18

the overall charge on an atom is ....

the number of ...... and ...... are equal

the overall charge on an atom is zero

the number of protons and electrons are equal

19

electrons are arranged in energy .... around the centre of the atom

the first energy .... is nearest to the centre and can take a maximum of .... electrons

the second and thur energy .... can take a maximum if .... electrons each

electrons are arranged in energy shells around the centre of the atom

the first energy shell is nearest to the centre and can take a maximum of 2 electrons

the second and thur energy shells can take a maximum if 8 electrons each

20

when atoms bond with other atoms, the number of electrons in their outermost energy shell ......

when atoms bond with other atoms, the number of electrons in their outermost energy shell changes

21

what are elements

substances that can’t be split into anything more simply by chemical means

22

what do all atoms in elements share?

the same atomic number

23

how are elements recognised in diagram?

the atoms have the same size or colour

24

what are compounds?

a combination of two or more elements in fixed proportions, joined together by strong bonds

25

does it matter if the compound is molecular, giant covalent or giant ionic?

no

26

what is a mixture?

the various components can be in any proportions

27

is an alloy a mixture? why?

yes because of the totally variable proportions

28

what is the differences in proportions between mixtures and compounds

A compounds proportions never vary

In a mixture the portions vary

If you wanted to mix some silvery zinc metal with some yellow sulphur, you could use any proportions

in zinc sulphide the proportions of zinc and sulphur have to be the exact same

29

what is the differences in properties between mixtures and compounds

in elements, each element has its own properties, but the properties of the compound are different

a mixture of hydrogen and oxygen would explode when you put it in a flame

a compound of hydrogen and oxygen to make water would put out a flame

30

what is the differences in ease of separation between mixtures and compounds

mixture can be separated by physical means

e.g. change in temperature, or dissolving part of the mixture in a solvent like water, things that do not involve chemical reactions

compounds have to be separated by chemical reactions

e.g. electrolysis

31

what is the differences in energy change between mixtures and compounds

there is little to no energy changes when making a mixture

there is greater energy changes when making a compound

32

explain why hydrogen is gas at room temperature

hydrogen is a simple molecule and so has weak intermolecular forces between its molecules

these weak forces break at room temperature

 

 

33

hydrogen chloride has a ...... molecular structure

there are .... forces between the ....

because of this, hydrogen chloride has a ..... boiling point

hydrogen chloride has a simple molecular structure

there are weak forces between the molecules

because of this, hydrogen chloride has a low boiling point

34

why is pure copper malleable?

pure metals are malleable because of their same sized atoms and arrangement

layers can easily slide over each other because in metals there are delocalised electrons which allow copper ions to do this

35

bronze is a mixture of tin and copper, the tin atoms are much bigger than the copper atoms

why is bronze not as malleable as copper

the different size of atoms (tin is much bigger than copper) mean that they can't slide over each other

36

why do metals conduct electricity?

delocalised electrons fall between the layer of atoms and conduct electricity

37

a substance has:

melting point =  540C

boiling point = 1200C

electrical conductivity as solid = poor

electrical conductivity as liquid = poor

electrical conductivity as aqueos solution = poor

what type of structure is it?

covalent: simple

38

a substance has:

melting point =  4030C

boiling point = 5670C

electrical conductivity as solid = good

electrical conductivity as liquid = good

electrical conductivity as aqueos solution = not soluble

what type of structure is it?

metallic

39

a substance has:

melting point =  -2100C

boiling point = -1960C

electrical conductivity as solid = poor

electrical conductivity as liquid = poor

electrical conductivity as aqueos solution = poor

what type of structure is it?

covalent: simple

CHECK

40

a substance has:

melting point =  16100C

boiling point = 22300C

electrical conductivity as solid = poor

electrical conductivity as liquid = poor

electrical conductivity as aqueos solution = not soluble

what type of structure is it?

covalent: giant

41

a substance has:

melting point =  6150C

boiling point = 8760C

electrical conductivity as solid = poor

electrical conductivity as liquid = good

electrical conductivity as aqueos solution = good

what type of structure is it?

ionic

42

a substance has:

melting point =  37270C

boiling point = 48270C

electrical conductivity as solid = good

electrical conductivity as liquid = good

electrical conductivity as aqueos solution = not soluble

what type of structure is it?

metallic

43

a substance has:

melting point =  560C

boiling point = 3420C

electrical conductivity as solid = good

electrical conductivity as liquid = good

electrical conductivity as aqueos solution = good

what type of structure is it?

metallic

44

a substance has:

melting point =  9340C

boiling point = 15680C

electrical conductivity as solid = poor

electrical conductivity as liquid = good

electrical conductivity as aqueos solution = insoluble

what type of structure is it?

ionic

45

a substance has:

melting point =  -1050C

boiling point = -450C

electrical conductivity as solid = poor

electrical conductivity as liquid = poor

electrical conductivity as aqueos solution = good

what type of structure is it?

covalent: simple

CHECK

46

state whether you would expect calcium flouride (ionic bonding) to have a high or low melting point and why

high

stronger attraction between the positive Cl atoms and negative F atoms

lots of energy needed

47

what is the chemical formula for Calcium Flouride

CaF2

48

what is the chemical formula for Potassium Bromide

KBr

49

what is the chemical formula for Barium NItrate

Ba(NO3)2

50

what is the chemical formula for Beryllium Oxide

BeO

51

what is the chemical formula for magnesium phosphate

Mg3(PO4)2

52

what does the '(II)' in Copper (II) indicate?

each copper atom contributes 2 electrons

53

why can copper conduct electricity?

because it has a sea of delocalised electronsnbetween the layers in the structure which are free to move

54

why can copper be drawn into wires

copper is ductile

the sea of delocalise delectrons mean the layers can slide easily over each other and be drawn into wires

55

what is a use for poly(ethene)

wax in polish

56

why does propanone and water (both simple molecular structures) have low boiling points

the attractive forces between their molecules are weak

these require little energy to be overcome

57

ammonia is:
ionic bonding / covalent bonding

insoluble in water / soluble in water

 

covalent bonding

soluble in water

58

methane is:
ionic bonding / covalent bonding

insoluble in water / soluble in water

covalent bonding

insoluble in water

59

poly(ethene) is:
ionic bonding / covalent bonding

insoluble in water / soluble in water

covalent bonding

insoluble in water

60

sodium chloride is:
ionic bonding / covalent bonding

insoluble in water / soluble in water

check

61

sodium hydroxide is:
ionic bonding / covalent bonding

insoluble in water / soluble in water

ionic bonding

soluble in water

62

give two observations made during the reaction between magnesium and oxygen

a huge bright light is seen

a sizzle is heard whilst the reaction occurs

63

why is the melting point of magnesium oxide much higher than that of sodium chloride?

lattice is held together by stronger attraction

this is because the ions have a higher charge and therefore a higher attraction

64

Suggest and explain why silica is used to make bricks for high-temperature furnaces. In your answer, you should refer to the structure of, and bonding im, silica

giant covalent stucture

strong covalent bonds between atoms

lots of energy to breka bonds - makes them suitable to withdstand heat

65

When glue sets it forms a giant covalent structure

explain why the giant covalent structures have high melting points?

they have strong covalent bonds which take a lot of energy to break so it needs to be a high heat to break these bonds