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Flashcards in Week 1 Deck (72)
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1
Q

Chemistry is the study of

A

matter

2
Q

Matter is

A

anything that takes up space

3
Q

A chemical change is

A

a chemical reaction - substances are used up and others are formed in their place

4
Q

An example of chemical change is

A

propane gas burning in the air - propane and oxygen are converted to carbon dioxide and water as they burn

5
Q

A physical change is

A

when matter doesn’t lose its identity - a common physical change is a change of state

6
Q

An example of a physical change is

A

ice melting. Ice is solid water, when it melts it is liquid water. It remains H20, there has been no chemical reaction - it is simply a change in state (the molecule still contains two hydrogen atoms and one oxygen atom)

7
Q

The three states of matter are

A

solid, liquid and gas

8
Q

Solid state

A
  • particles are close together and there are strong interactions between the particles
  • the movement of particles is very slow
  • there is definite shape and volume
    examples - ice, salt, iron
9
Q

Liquid state

A
  • particles are close together but not as close as a solid
  • not fixed like a solid but it is random
  • strong but not as strong as a solid
  • takes the shape of the container
  • has no definite shape but a definite volume
    examples - water, oil, vinegar
10
Q

Gas state

A
  • particles are loosely packed and very far apart from each other
  • gaseous particles don’t have any interactions
  • expands to fill the container it is put into
  • has no definite shape or volume
    examples - water vapour and air
11
Q

The difference between a mixture and a pure substance is that

A

a pure substance can not be further purified whereas a mixture is a combination of two of more pure substances

12
Q

An element is

A

a substance that consists of identical atoms.
examples - carbon, hydrogen, iron
An element can not be subdivided by chemical or physical means. Elements are all the things that are found on the periodic table

13
Q

How many elements have been identified

A

166 - of these 88 occur in nature the others have been made by chemists and physicists.

14
Q

Each element is abbreviated by

A

a symbol which consists of one or two letters

15
Q

The first letter of the chemical symbol is always a

A

capital

16
Q

The second letter of the chemical symbol

A

if there is one is not a capital

17
Q

The chemical symbol for hydrogen (1)

A

H

18
Q

The chemical symbol for helium (2)

A

He

19
Q

The chemical symbol for lithium (3)

A

Li

20
Q

The chemical symbol for beryllium (4)

A

Be

21
Q

The chemical symbol for boron (5)

A

B

22
Q

The chemical symbol for carbon (6)

A

C

23
Q

The chemical symbol for nitrogen (7)

A

N

24
Q

The chemical symbol for oxygen (8)

A

O

25
Q

The chemical symbol for fluorine (9)

A

F

26
Q

The chemical symbol for neon (10)

A

Ne

27
Q

The chemical symbol for sodium (11)

A

Na

28
Q

The chemical symbol for magnesium (12)

A

Mg

29
Q

The chemical symbol for aluminium (13)

A

Al

30
Q

The chemical symbol for silicon (14)

A

Si

31
Q

The chemical symbol for phosphorus (15)

A

P

32
Q

The chemical symbol for sulfur (16)

A

S

33
Q

The chemical symbol for chlorine (17)

A

Cl

34
Q

The chemical symbol for argon (18)

A

Ar

35
Q

The chemical symbol for potassium (19)

A

K

36
Q

The chemical symbol for calcium (20)

A

Ca

37
Q

The chemical symbol for gold (79)

A

Au

38
Q

The chemical symbol for silver (47)

A

Ag

39
Q

The chemical symbol for lead (82)

A

Pb

40
Q

A compound is

A

a pure substance made up of two or more elements in a FIXED RATIO mass.
Compounds include - sodium chloride, water, glucose
The formula of a compound tells us the rations of its constituent elements and identified each element by its atomic symbol.
NACL (sodium chloride = 1 sodium atom + 1 chlorine atom)

41
Q

NACL

A

sodium chloride = 1 sodium atom + 1 chlorine atom

42
Q

H20 (numbers should be subscript)

A

the 2 is subscript which indicates there is a fixed ratio of 2 hydrogen atoms (H) for 1 oxygen atom (O)

43
Q

C6H12O6 (numbers should be subscript)

A

6 carbon (C) 12 hydrogen (H) 6 oxygen (O)

44
Q

A heterogeneous mixture is a

A

non uniform composition
examples:
- noodle soup (noodles in water)
- blood (liquid with suspended particles which are red blood cells)
- muddy water - mud particles floating in water

45
Q

a homogenous mixture is a

A

uniform composition
examples:
- water and salt (uniform composition)
- sea water (you don’t see the salt and the water)

46
Q

three points central to Dalton’s atomic theory

A

1) all matter is composed of tiny particles
2) compounds are formed by the chemical combination or two or more different kinds of atoms
3) a molecule is a tightly bound combination of two or more atoms that act as a single unit

47
Q

The law of conservation of mass

A

in ordinary chemical reactions, no element disappears or is changed into an atom of another element.
Matter can neither be created or destroyed. A chemical reaction just changes the attachments but does not destroy the atoms themselves.
example carbon monoxide (C+O) + lead oxide (Pb+O) = carbon dioxide (O+C+O) + lead (Pb)

48
Q

what is the difference between a monoatomic, diatomic and polyatomic molecule?

A
monoatomic elements - single atoms (mono means one)
examples helium (He) and neon (Ne)

diatomic elements - two atoms (di means two)
examples - H2, N2, O2, F2 (numbers should be subscript)

polyatomic - have three or more atoms per molecule (poly means many)
examples - O3, P4, S8 (numbers should be subscript)

49
Q

The three subatomic particles and their charges are:

A

Protons: +1 charge
Electrons: -1 charge
Neutrons: 0 charge

50
Q

diagram of the atom showing the protons, neutrons and electrons

A

insert diagram from notes here

51
Q

The atomic number is

A

the number of protons in the nucleus of the atom

52
Q

Isotopes are

A

atoms with the same number of protons but a different number of neutrons
- Carbon-12 has 6 protons and 6 neutrons
- Carbon-13 has 6 protons and 7 neutrons
- Carbon-14 has 6 protons and 8 neutrons
Most elements on earth are a mixture of isotopes
(isotopes are similar to identical twins that have a different mass)

53
Q

Mass number is

A

the sum of the number of protons in the nucleus of an atom

54
Q

Atomic weight is

A

the weighted average of the masses (in amu) of the naturally occurring isotopes of an element

55
Q

Periods in the periodic table are arranged in

A

horizontal rows

56
Q

Groups in the periodic table are arranged in

A

vertical rows

57
Q

Elements in groups have similar

A

recurring sets of properties

58
Q

List two properties of non-metals

A
  • lie on the right side of the periodic table (except hydrogen)
  • in chemical reactions they tend to accept electrons
  • dull, not shiny
  • they are brittle and will shatter if hit with a hammer
59
Q

List two properties of metals

A
  • are solid at room temperature (except mercury)
  • shiny
  • conduct electricity
  • ductile and malleable
60
Q

List two properties of metalloids

A
  • share the properties of metals and non-metals
  • there are 6 elements classed as metalloids (boron, silicon, germanium, arsenic, antimony, and tellurium
  • example, antimony is shiny like a metal but if you hit it with a hammer it will shatter. It is a poor conductor of electricity, it has a melting point so it shares the properties of a metal and non metal.
61
Q

where are alkali metals found on the periodic table

A

in group 1a

62
Q

where are alkaline earth metals found on the periodic table

A

in group 2a

63
Q

where are transition metals found on the periodic table

A

in the section containing all the b elements (also called the d block)

64
Q

where are halogens found on the periodic table

A

in group 7a

65
Q

where are noble gases found on the periodic table

A

in group 8a

66
Q

where are lanthanide metals found on the periodic table

A

directly underneath the main body of the periodic table - elements 57 through to 71

67
Q

where are actinide metals found on the periodic table

A

underneath the main body of the periodic table, the second row contains the actinide metals, elements 89 through to 103

68
Q

the electron configuration shows

A

the arrangement of electrons in the extranuclear space

69
Q

the ground state electron configuration is the

A

lowest energy state of an atom

70
Q

all group 1A elements have how many valance electrons in their outer shell

A

1

71
Q

all group 8A elements have how many valance electrons in their outer shell

A

all 8A elements have a full complement of electrons in their outer shell as they are all stable elements

72
Q

electron configuration

A

1s2
2s2, 2p6,
3s2, 3p6,
4s2, 3d10, 4p6