Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Yr8-Science > y9 Science revision > Flashcards

y9 Science revision Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

define an element

A

contains only one type of atom

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

define a compound

A

two or more different atoms chemically joined/ bonded together

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

define a mixture

A

two or more different elements or compounds NOT chemically joined/ bonded together.

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

define an atom

A

smallest particle of an element that is involved in a chemical reaction

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

define a molecule

A

two or more atoms chemically joined/ bonded together

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

what is shown on the left side of a chemical reaction?

A

reactants

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

what is shown on the right side of a chemical reaction

A

products

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

write a word equation for the formation of water from the reaction between hydrogen and oxygen

A

hydrogen + oxygen —> water

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

write a symbol equation for the formation of water from the reaction between hydrogen and oxygen

A

H2 + O2 —> H2O

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

define a solute

A

a substance that dissolves in a solvent

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

define a solvent

A

liquid that can dissolve a solute

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

define a solution

A

a mixture of a solute and solvent

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

how can an insoluble solid be separated from a liquid?

A

filtration

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

how can a soluble solid be separated from a solution

A

evaporation then crystallisation

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

how can immiscible (don’t mix) liquids be separated?

A

Use a pipette to extract one layer of liquid

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

how can miscible (do mix) liquids be separated?

A

distillation

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

what physical property is used in distillation?

A

boiling points - separates at different temperatures

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

what are the 3 steps in distillation?

A

evaporate, condense and collect

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

what is chromatography?

A

separates colours in mixture

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

what are the 5 models of the atom?

A

Tiny spheres, Plum pudding,Nuclear, Bohr’s and today’s model

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

who was responsible for each model of the atom?

A

J Dalton - Tiny spheres, JJ Thomson - Plum pudding, E Rutherford - Nucleus, Niels Bohr - Bohr’s, J Chadwick - Today’s model

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

describe the plum pudding model

A

solid ball of positive charge with electrons embedded throughout it

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

describe the nuclear model

A

positive nucleus at the centre, with electrons at the edge of the atom - rest is empty space

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

what evidence gave the nuclear atom as mainly empty space?

A

Positive Helium nucleus (alpha particle) fired at a gold foil - many went straight through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what evidence gave the nuclear atom as having a positive nucleus?

A

Positive Helium nucleus (alpha particle) fired at gold foil - some slightly deflected as they went past the edge of the nucleus. Those fully deflected were repelled by the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what did Bohr’s model change about the nuclear model?

A

Electrons were no longer at the edge of the atom but in energy shells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

how did today’s atomic model change from Bohr’s?

A

Discovery of neutrons, now added these to the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is the order of the discovery of the sub atomic particles?

A

Electron, proton then neutron last

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is the mass of each sub atomic particle?

A

Proton = 1, Electron = almost one, Neutron = 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is the charge on each subatomic particle?

A 
Protons = +1
Electrons = -1
Neutrons = 0
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

where is most of the mass of an atom found?

A

in the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what subatomic particles are found in the nucleus?

A

protons and neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

where are electrons found?

A

in energy shells orbiting the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

why does the atom have no overall charge?

A

number of protons = number of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what does the relative atomic mass represent?

A

protons and neutrons

36
Q

what does the atomic number represent?

A

Number of protons = number of electrons

37
Q

how do you calculate the number of neutrons in an element?

A

Mass number - Atomic number

38
Q

what are the numbers of electrons allowed in the electron shells?

A

1st she’ll = 2 electrons, 8 electrons are allowed in every shell after that

39
Q

what is the electron configuration showing?

A

the number of electrons in each shell (e.g. 2,6)

40
Q

Define an isotope?

A

Atoms are the same elements with a different number of neutrons

41
Q

Approximately how large are atoms?

A

Radius is about 0.1nm

42
Q

how large is the nucleus compared to the whole atom?

A

about 1/10000 the size

43
Q

What is abundance?

A

The % of atoms in a sample with a particular mass

44
Q

in the modern periodic table, how are the atoms arranged?

A

By their atomic number and in groups according to chemical properties

45
Q

why do elements in the same group have similar properties?

A

because they all have the same number of electrons in their outer shell

46
Q

before the discovery of protons, neutrons and electrons, how did scientists organise the elements?

A

by their atomic weight

47
Q

why did Mendeleev leave gaps in his periodic table?

A

for elements that had not yet been discovered

48
Q

which discovery meant that organising elements by their atomic weight not always correct?

A

Isotopes

49
Q

where are metals on the periodic table found?

A

to the left and bottom of the periodic table

50
Q

what are the names of groups 1, 7 & 0?

A

1 = Alkali metals, 7 = Halogens, 0 = Noble gases

51
Q

why are noble gases inert (unreactive)?

A

they have a full outer shell of electrons so don’t need to lose or gain electrons to be stable

52
Q

what does the group number tell you?

A

number of electrons in outer shell

53
Q

what does the period number tell you?

A

number of electron shells

54
Q

give some properties of group 1 metals

A

silver coloured, shiny, soft and very reactive

55
Q

why are group 1 metals more reactive as you go down the group?

A

larger atoms so outer electron is further away from the attractive positive nucleus, so electron is more easily lost

56
Q

what do group 1 metals produced when added to water?

A

Metal Hydroxide + Hydrogen

57
Q

are halogens metals or non - metals?

A

non - metals

58
Q

why are group 7 halogens more reactive as you go up the group?

A

smaller atoms so outer electron is closer to the attractive positive nucleus, so easier to attract an electron

59
Q

what is the central block in the periodic table called?

A

transition metals

60
Q

compare the hardness of group 1 & transition metals

A

Transition metals are much harder than group 1 metals

61
Q

state which cell is smaller: a prokaryote cell or eukaryote cell

A

prokaryotic

62
Q

give one example of a prokaryotic cell and two examples of eukaryotic cells

A 
Prokaryotic = bacteria 
Eukaryotic = animal and plant cells
63
Q

state 2 small similarities between a prokaryotic and eukaryotic cell

A

Both have a cytoplasm

Both have a cell membrane

64
Q

state one difference between prokaryotic and eukaryotic cell

A

eukaryotic cells have genetic material enclosed in a nucleus
Prokaryotic cells do not have genetic material enclosed in a nucleus. It is a single DNA loop

65
Q

Parts of a bacterial cell

A 
cell membrane 
cell wall
circular strand of DNA
Plasmid 
Cytoplasm
66
Q

state how you convert from centimetres (cm) to millimetres (mm)

A

times by 10

67
Q

state how you covert from millimetres (mm) to micrometers ( um)

A

times by 1000

68
Q

what is the function of a nucleus

A

contains genetic information in the form of chromosomes and controls the activities of the cell

69
Q

what is the function of the cytoplasm?

A

where many chemical reactions occur in a cell. It contains many enzymes for these reactions

70
Q

what is the function of a cell membrane?

A

partially permeable; controls the movement of substances into and out of the cell

71
Q

what is function of a mitochondria?

A

this is the site of aerobic respiration and release of energy

72
Q

what is the function of a ribosome?

A

this is the site of protein synthesis

73
Q

what is the function of a chloroplast?

A

Contains a green pigment called chlorophyll which absorbs light for photosynthesis

74
Q

what is the function of a vacuole?

A

stores sap ( a weak solution of salts and sugars)

75
Q

what is the function of a cellulose cell wall?

A

Rigid; supports and strengthens the cell

76
Q

what is the function of a plasmid?

A

a small ring of additional DNA found in bacteria

77
Q

state three organelles that present in a plant cell that are not present in an animal cell?

A

chloroplast
vacuole
cellulose cell wall

78
Q

state one organelle that is present in both bacteria and plant cells

A

cell wall (however only the plant cell wall is made of cellulose) Or cell membrane Or cytoplasm

79
Q

state two. differences between a bacterial cell (prokaryote) and a plant cell (eukaryote)

A

plant cells contain genetic information in a nucleus and bacteria do not
plant cells contain mitochondria and bacteria do not

80
Q

recall the equation for calculating magnification

A

magnification = size of image/ size of object (actual size)

81
Q

describe and explain the function of sperm cells as a specialised cell

A

contain many mitochondria in their mid - piece for energy to move. Have a flagellum (tail) to swim towards the egg cell

82
Q

describe and explain the function of muscle cells as a specialised cell

A

contain many mitochondria which supplies energy for muscle contraction

83
Q

describe and explain the function of root hair cells as a specialised cell

A

contain many mitochondria to supply energy for active transport of ions

84
Q

describe and explain the function of leaf palisade cells as a specialised cell

A

contain many chloroplasts which contains chlorophyll to absorb light for photosynthesis

85
Q

describe and explain the function of xylem as a specialised cell

A

dead, hollow cells with no cytoplasm that join to end to end to form xylem tubes for the transport of water freely up the plant. The cell walls are strengthened with lignin

86
Q

describe and explain the function of phloem as a specialised cell

A

cells joined end to end to form phloem tubes. Phloem cells have very few organelles e.g. no mitochondria to allow more room for the transport of cell sap

Yr8-Science (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions