T1 atomic structure and the periodic table Flashcards

1
Q

what is an atom

A

smallest part of an element what can exist

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

what is an element

A

substance of only one type of atom

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

what 2 groups can elements be classified into

A

metals and non-metals

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

what is a compound

A

two or more elements combined chemically in fixed proportions which can be represented by formulae

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

do compounds have the same properties as their constituent elements

A

no, they have different properties

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

what is a mixture?

does it have the same chemical properties as its constituent materials?

A

mixture consists of two or more elements or compounds not chemically combined together

does have the same chemical properties

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

what are the methods through which mixtures can be separated

do these involve chemical reactions

A

filtration, crystallisation, simple distillation, fractional distillation, chromatography

don’t involve chemical reactions

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

describe and explain simple distillation

A

used to separate liquid from a solution - the liquid boils off and condenses in the condenser

thermometer will read the boiling point of the pure liquid, get to keep the liquid

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

describe and explain crystallisation

A

solution is heated and some of the solvent evaporates, leaving behind a saturated solution

saturated solution is allowed to cool and crystals to form

crystals can be separated by filtration

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

describe and explain evaporation

A

technique for separation of a solid dissolved in a solvent from a solvent (eg salt from H2O)

solution is heated until all the solvent evaporates, the solids stays in the vessel

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

describe and explain fractional distillation

A

technique for separation of a mixture of liquids, works when liquids have different boiling points

the fractionating column contains glass beads, helps to separate the compounds

industry - mixtures are repeatedly condensed and vapourised

column is hottest at bottom and coldest at top

liquids will condense at different heights

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

describe and explain chromatography

A

place a piece of paper with a spot containing a mixture in a beaker with some solvent

bottom of paper has to be in contact with the solvent

solvent level will slowly start to rise, separating the spot into few spots

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

what is a separating funnel

A

apparatus for separating immiscible liquids

two immiscible liquids of different densities will form two distinct layers in the separatory funnel

can run off the bottom layer (liquid with greater density) to a separate vessel

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

describe the plum-pudding model

A

atom is a ball of positive charge with negative electron embedded in it

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

describe the Bohr/nuclear model and how it came about

A

suggests that electrons orbit the nucleus at specific distances (shells) - came about from the alpha scattering experiments

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

what did the work of James Chadwick provide evidence for

A

existence of neutrons in the nucleus

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

relative masses and relative charges of the proton, neutron and electron

A

Masses: 1, 1, very small
charges: 1, 0, -1

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

radius of an atom

A

0.1 nm

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

radius of a nucleus and what is it compared to that of the atom

A

1x10-14 m and 1/10000

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

name given to the number of protons in the nucleus

A

atomic number

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

atoms of the same element have the same number of which particle

A

protons

22
Q

what is the mass number

A

total number of protons and neutrons

23
Q

equation for the number of neutrons using mass number and atomic number

A

subtract atomic number from the mass number

24
Q

what is an isotope

do isotopes of an element have the same chemical properties

A

atoms of the same element that have a different number of neutrons

have the same chemical properties as they have the same electron structure

25
Q

what is the relative atomic mass

A

average mass value which takes the mass and abundance of isotopes of an element into account, on a scale where mass of 12C is 12

26
Q

what are ions

A

charged particles

formed when atoms lose (positive ions) electrons or gain (negative ions) electrons

27
Q

properties of metals

A
high boiling/melting point
conducts heat and electricity
shiny
malleable
high density
basic oxides
28
Q

properties of non-metals

A
low boiling/melting point
don't conduct heat or electricity - minus graphite
dull
brittle
low density
acidic oxides
29
Q

what is formed when a metal reacts with a non-metal

A

ionic compound (made of positive and negative ions)

30
Q

what is formed when a non-metal reacts with a non-metal

A

molecular compound containing covalently bonded atoms

atoms share electrons, as opposed to transferring electrons between each other

31
Q

group 0 elements are known as

A

noble gases

32
Q

what makes the periodic table periodic

A

similar properties of elements occur at regular intervals

33
Q

elements in the same group have the same number of electrons in their outer shell; what does this tell us about their chemical properties

A

they have similar chemical properties

34
Q

early periodic tables were arranged by

A

increasing atomic mass

35
Q

knowledge of what made it possible to explain why the order based on atomic weights was not always correct

A

isotopes

36
Q

elements that react to form positive ions are

A

metals

37
Q

elements in group 1 are known as

A

alkali metals

38
Q

state three characteristics of the alkali metals

A

1 electron in outer shell
low density
are stored under oil to prevent reactions with oxygen or water
soft, can be cut with a knife

39
Q

how do group 1 elements react with non-metals

why are these reactions similar for the different group 1 elements

A

form ionic compounds which are soluble white solids which form colourless solutions

all have 1 electron in outer shell

40
Q

how do group 1 elements react with water

A

release hydrogen and form hydroxides which dissolve to form alkaline solutions

react vigorously with water fizzing and moving around on the surface of water

41
Q

how does reactivity change moving down group 1

why

A

increases as the atoms get larger and the distance between the nucleus and the outer electrons increases thus, the attraction from the nucleus decreases, allowing them to easily lose electrons

42
Q

state 5 characteristics of group 7

A
7 electrons in outer shell
coloured vapours
diatomic molecules
form ionic salts with metals
form molecular compounds with non-metals
43
Q

state 5 group 7 elements and states of matter of molecules they form

A

F2 is a pale yellow gas
Cl2 is a pale green gas
Br2 is a dark brown liquid
I2 is a grey solid

44
Q

state 3 changes that occur in group 7 as one moves down the group

A

higher relative molecular mass
higher melting and boiling point
less reactive - less easily gain electrons

45
Q

a more reactive halogen displaces a less reactive one from an aqueous solution of iits salt; explain the trend in reactivity of halogens in these reactions

A

reactivity decreases down the group

as we go down the group, the atoms get larger, so an incoming electron will be less tightly held by the attractive forces from the nucleus

46
Q

compare group 1 metals and transition metals

A

G1 and transition metals are heat and electricity conductors, shiny when polished and form ionic compounds with non-metals

transition metals have higher densities and higher melting points, less reactive and harder than group 1 metals

47
Q

state 3 common characteristics of transition metals

A

ions with different charges
coloured compounds
catalytic properties

48
Q

what is a catalyst

A

chemical substance that increases the rate of a chemical reaction

not used up over the course of the reaction

49
Q

state the colours of flames observed when lithium, sodium and potassium burn in oxygen

A

crimson-red : Li
yellow-orange: Na
lilac: K

50
Q

describe the properties of noble gases

discuss the trends in properties down the group

A

non-metals, gases, low boiling point, unreactive (full outer shell so don’t easily accept or lose electrons)

boiling point increases down the group, as atoms get heavier