S3 EXAM Flashcards Preview

Chemisty > S3 EXAM > Flashcards

Flashcards in S3 EXAM Deck (50):
1

Mono

One

2

Di

Two

3

Tri

Three

4

Tetra

Four

5

What substances form together to make ionic bonds

Metal and non-metals

6

Ionic bonding

It is an electrostatic force of attraction between oppositely charged ions

7

Strength of ionic compound

Strong

8

Why do atoms gain or lose electrons

They are more stable with a full outer shell of electrons

9

What happens when metal atoms form ions

They lose an electron to form positive ions

10

How do you work out how many electrons a metal loses when when it forms an ion

Why do metal ions do this

A metal loses electrons equal to the number of electrons in the outer shell

They are more stable with a full outer shell of electrons

11

What happens to non-metal atoms when they form ions

They always gain electrons to become megitive ions

12

What substances have metallic bonding

Metals

13

Metallic bonding

Electrostatic attraction between positively charged atom cores or ions and delocalised electrons

14

Strength of metallic bonds

Strong

15

What elements form covalent bonds

Non-metal atoms

16

Covalent bonds

Shared pair of electrons

17

What holds the atoms together in covalent bonds

The shared pair of electrons is attracted to both positive nuclei

18

What is a molecule

A group of atoms held together by covalent bonds

19

What is a diatomic molecule

A molecule that contains two atoms

20

What is meant by a discreet molecular substance

One that exists with separate molecules

21

Strength of covalent bonds

The covalent bonds inside molecules are strong whereas the forces of attraction are week

22

Covalent network

A giant structure where atoms are covalently bonded together e.g silicon, carbon, graphite

23

Electric current

A floe of charged particles

24

What charged particles can carry a current

Freely moving/delocalised electrons or ions

25

Why do covalent compounds not conduct electricty

Covalent compounds consist of molecules that are unchanged, they contain no charged particles to carry an electric current

26

In what state will ionic compounds conduct

Ionic compounds don't conduct in solid state but when molten or dissolved in water

27

Why do metals have high melting and boiling points

Strong metallic bonds are broken as metals melt and boil. These bonds are strong as the delocalised electrons are attracted to many surrounding positive ion cores

28

Why do ionic compounds have a high melting and boiling point

Strong ionic bonds must be broken as ionic compounds melt and boil. The ionic bonds are strong as there is a strong electrostatic force of attraction between positive and negative ions

29

Why do covalent network structures have high melting and boiling point

Only the weak forces of attraction between molecules are broken when these substances melt/biol. the strong covalent bonds in the molecule are NOT broken

30

How soluable are ionic substances in water

They are usually souable

31

What is a vertical columb of element called in the periodic table

A group

32

What is a horizontal group of elements called

A period

33

In what ways are elements that are in the same group similiar

Similar chemical properties

Same number of electrons on outer shell

34

Alkali metals

Very reactive metals

35

Halogens

Very reactive non-metals

36

Noble gasses

Very unreactive non-metals

37

Why are atoms neutral

They contain the same amount of positive protons and negative electrons

38

What is used to put the elements in order in the periodic table

In order of atomic mass

39

What is the atomic number

The number protons in the nucleus

40

What is the mass number

The number proton plus neutrons in the nucleus

41

How to calculate the number of netrons

Mass number - atomic mass

42

What is an isotope

Atoms of the element with different mass numbers but same atomic number

43

Relative atomic mass

The average mass of an element taking into propotion/ abundance of each isotope present

44

4 factors that can effect the rate of a chemical reaction

Concentration
Temperature
Particle size
Catalyst

45

Collision theory

In order for a reaction to take place reactant particles must collide with each other

46

Catalyst

A catalyst is a substance that can be added to a chemical reaction to increase the rate. Without getting used up

47

4 ways to measure the rate of chemical reactions

Measure volume of gas collected
Measure mass loss
Measure pH change
Measure colour change

48

Why do acids conduct electricity

Acids produce the hydrogen ion when dissolved in water. These ions when in water act as charge carriers and conduct

49

What type of bonding do acids have

Ionic bonding

50

Why do alkalis conduct electricity

They contains hydroxide ion. Theses ions conduct electricity