Science YR8 Flashcards

1
Q

What are forces?

A

Just pushes and pulls in a particular direction

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

What are balanced forces?

A

Two forces acting on an object can also work against each other if they are in oppoisite directions. If the two forces are the same, nothing will change.

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

What are unbalanced forces?

A

If one of the forces is stronger than the other, something will start to move. the forces are unbalanced. If the unbalanced forces are acting on a moving object, the object will change its speed.

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

What does stationary mean?

A

Something that is still or not moving

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

What does steady speed mean?

A

Something moving at a constant pace.

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

What are contact forces?

A

When a force is applied on an object with some sort of contact or touch.

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

What are noncontact forces?

A

When a force is applied on an object without any contact or touch.

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

What is friction?

A

A force between two surfaces that are sliding, or trying to slide, across each other. It always works in the direction opposite to the direction in which the object is moving. It always slows a moving object down. It also produces heat.

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

What is air resistance?

A

A type of friction between air and another material.

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

What is water resistance?

A

The friction between your skin and the water particles.

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

What is gravity?

A

The force that pulls things to the centre of Earth (and other planets).

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

What is magnetic forces?

A

When two magnets are close, they create pushing or pulling forces on one another.

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

What is floating?

A

Object that sits above the fluid.

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

What is sinking?

A

Object that moves downwards in the fluid.

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

What is upthrust?

A

Force of a fluid pushing objects upwards.

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

What is buoyant?

A

If the weight is equal to or less than the upthrust, it floats. Things that floats are buoyant.

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

What are fluids?

A

Substances that flow- liquids and gases.

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

What is density?

A

How hard or soft an object is.

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

What does physical changes mean?

A

When a substance changes shape, size and state of the matter BUT the particles themselves do not change only their spacing and movement change.

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

What does chemical changes mean?

A

The particles change completely making a new substance.

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

What is the change from liquid to gas called?

A

Evaporation

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

What is the change from gas to solid called?

A

Deposition

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

What is the change from solid to liquid called?

A

Melting

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

What is the change from liquid to solid called?

A

Freezing

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

What is the change from solid to gas called?

A

Sublimation

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

What is the change from gas to liquid called?

A

Condensation

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

What does pressure mean?

A

The amount of force (N) pushing on a certain area.

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

How do you increase the pressure in fluids?

A

-Increasing the number of particles
-Increasing speed of particles by heating the fluid-gives energy
-Compress-decrease container size

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

What is the formula for density?

A

mass / volume

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

What is the formula for volume?

A

mass / density

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the formula for mass?

A

density x volume

32
Q

What is the formula for weight (N)?

A

mass(g) x 10

33
Q

What is the formula for pressure?

A

force / area N / m2

34
Q

What does elastic mean?

A

Something that changes shape when a force acts on it AND then returns to its origional shape.

35
Q

What does stretch and extension mean?

A

How far something has been made longer. The difference between a springs original length and its stretched length.

36
Q

What does compress mean?

A

How far something is made shorter.

37
Q

What is Hooke’s Law?

A

The extension (stretch) of a spring is proportional to the force applied UP TO its limit of proportionality. This means for every 1N increase in the force, the spring will extend by the same length.

38
Q

What does lubricants mean?

A

Substances that are added between surfaces to reduce (decrease) friction.

39
Q

What are some physical properties of substances?

A

-Colour
-Shape
-State of matter
-Malleable
-Brittle
-Melting and boiling points
-Density
-Conducting heat and electrisity

40
Q

What are some chemical properties of substances?

A

-Reactivity
-Flammability

41
Q

What are some signs that a reaction has occured?

A

-Gas being produced (smoke, bubbles)
-Sound, noises
-Colour change
-Flame, sparks, heat produced
-Change of pH

42
Q

What is a triad?

A

A group of 3 elements that have very similar properties.

43
Q

What is a trend?

A

A pattern or a tendency to increase/ decrease/ stay the same in a series of data

44
Q

What does reactivity mean?

A

Property of participating in chemical reactions. The more reactive, the more intense and quick the reaction is.

45
Q

What way are the groups?

A

Vertical

46
Q

What way are the periods?

A

Horizontal.

47
Q

What elements are in the first Period?

A

Hydrogen and helium

48
Q

What are the elements in group 0 called?

A

Noble Gases

49
Q

What are the elements in group 7 called?

A

Halogens

50
Q

What are the elements in group 1 called?

A

Alkali metals

51
Q

What is an element?

A

One type of atom in a substance.

52
Q

What is a compound?

A

A substance made up of two or more different elements chemically bonded together

53
Q

What is a mixture?

A

A substance consisting of two or more substances not chemically combined together.

54
Q

What is a molecule?

A

Two or more atoms from the same element chemically bonded together.

55
Q

What is the difference between a compound and a mixture?

A

A compound are two atoms chemically bonded whereas a mixture the atoms aren’t.

56
Q

What are some physical properties of a substance?

A

-Colour
-Melting point
-Boiling point
-Density
-Strength
-Flexibility
-Conduction of heat
-Conduction of electrisity

57
Q

Melting (solid-liquid)

A

Heating-increased energy-particles vibrate more-particles start to break free of the structure and move around.

58
Q

What is drag?

A

The resistance force that goes against an object as it moves through a fluid.

59
Q

What is the name of group 0?

A

Nobal gases

60
Q

What is the name of group 7?

A

Halogens

61
Q

What is the name of group 1?

A

Alkali metals

62
Q

What elements are in period 1?

A

Hydrogen and helium

63
Q

What is the name of the horizontal rows on the periodic table?

A

Periods

64
Q

What is the name of the vertical rows on the periodic table?

A

Groups

65
Q

What is an atom?

A

The smallest part of an element that can exist.

66
Q

What are some properties of metals?

A

-shiny
-good conductor of heat
-good conductor of electricity
-high density
-malleable
-ductile
-oxidised form alkaline solutions.

67
Q

What are some properties of non-metals?

A

-dull
-poor conductors of heat
-poor conductors of electricity
-low density
-brittle
-oxidised form acidic solutions.

68
Q

What are some properties of alkali metals?

A

-Solids at room temperature
-Very reactive
-Good conductors of heat
-Good conductors of electricity
-soft
-shiny when cut
-low density

69
Q

What are some properties of halogens?

A

-some solids, a liquid and some gases at room temperature
-very reactive
-poor conductors of heat
-poor conductors of electricity
-solids are brittle
-low density

70
Q

What are some properties of noble gases?

A

-gases at room temperature
-unreactive
-poor conductors of heat
-poor conductors of electricity
-low density

71
Q

What things increase as you move down Group 1, Group 7 and Group 0?

A

-Atomic radius
-Atomic number
-Density
-atomic mass

72
Q

What is room temperature?

A

25 C

73
Q

What is the boiling point of water?

A

100 C

74
Q

What is the freezing point of water?

A

0 C

75
Q

Where is the atomic mass located?

A

Underneath the element symbol.

76
Q

Where is the atomic number located?

A

Top left hand corner.