8th Grade Science Test 1 Flashcards

1
Q

measures the pull of gravity on an object

A

weight

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

a good scientific experiment includes

A

several constant factors and one variable

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

substances composed of only one type of atom

A

elements

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

in order for soil to drain well and not retain excess water, it must contain

A

sand

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

humus is formed as a result of

A

decomposition

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

the type of soil that contains a mixture of sand, silt, clay, and humus

A

loam

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

primary plant food element found in the ashes of burned fruits

A

potassium

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

a substance having a pH of 10 would be

A

basic

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

a theory that has never been proven false

A

law

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

a fertilizer bag labeled 10-8-14 would contain 10% of the element

A

nitrogen

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

measures the amount of matter in an object

A

mass

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

plants that have short stems, few leaves, and a pale green color need the plant food element

A

nitrogen

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

the plant food element that a farmer should apply when his crop begins to ripen

A

phosphorus

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

nitrates are formed by

A

lightning, nitrifying bacteria, nitrogen-fixing bacteria

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

legumes allow nitrogen-fixing bacteria to form swellings called ___ on their roots

A

nodules

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

measures how tightly packed matter is

A

density

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

a sensible explanation to a scientific problem

A

hypothesis

18
Q

substances composed of two or more elements bonded together

A

compounds

19
Q

the primary plant food elements

A

nitrogen
phosphorus
potassium

20
Q

when scientists perform experiments, they record facts and information called

A

data

21
Q

the study of soil

A

pedology

22
Q

the study of matter and movement of God’s physical creation

A

science

23
Q

to express acidity and basicity of substances, chemists use the

A

pH scale

24
Q

the upper surface of ground water

A

water table

25
Q

soil and porous rock that cannot hold any more water are said to be

A

saturated

26
Q

List the six steps of the scientific method.

A
  1. State the problem.
  2. Gather information about the problem.
  3. Formulate a hypothesis.
  4. Test the hypothesis by designing and performing an experiment.
  5. Record and analyze any changes during the experiment.
  6. State the conclusions.
27
Q

any soil material primarily derived from from living organisms

A

organic

28
Q

any soil material primarily derived from nonliving matter

A

mineral

29
Q

breakdown of organisms

A

decompose

30
Q

substance composed of decayed organisms’ particles

A

humus

31
Q

reusing old materials

A

recycling

32
Q

process that breaks rocks down into soil

A

weathering

33
Q

top 2 to 6 inches of soil

A

topsoil

34
Q

layer of solid rock below the soil

A

bedrock

35
Q

the substance of the physical world

A

matter

36
Q

an area of ground water collected in a layer of rock or soil

A

aquifer

37
Q

a “self-pumping” well

A

artesian well

38
Q

the upward movement of water through a tiny space in response to surface tension

A

capillarity

39
Q

the most basic units of matter

A

atoms

40
Q

the air pockets that are found in the soil

A

pore spaces

41
Q

Describe the nitrogen cycle, why it is important to plants, an done way in which nitrogen compounds are formed.

A
The nitrogen cycle is the movement of nitrogen from the air to the soil to be used by plants and then returned to the atmosphere to be used again.
The nitrogen cycle is important because plants cannot use the form of nitrogen that is in air unless it is combined with other elements to form certain compounds.
Nitrogen compounds (specifically nitrates) are formed when lightning causes nitrogen and oxygen to form compounds that are carried to the soil by rain.
Nitrogen compounds are formed by nitrogen-fixing bacteria