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Flashcards in Semester 1 Study Guide Deck (63):
1

Scientific Method

a sequence of events used to test a question

2

Hypothesis

an explanation of how something happens

3

Independent Variable

a factor that changes in an experiment

4

Dependent Variable

a factor that changes as a result of the IV changing

5

Constant

a factor the remains the same in an experiment

6

Control Group

an unchanged experiment that is used to compare to other experiments

7

Bar/column graph is used for ________

comparing data

8

Line graph is used for _________

data over time

9

Pie chart is used for ___________

comparing data that is part of a whole

10

What are the three types of models?

1. physical
2. mathematical
3. conceptual

11

Identify the benefits and limitations of models.

benefits: can model things that don't exists; can be kind of like a hypothesis

limitations: don't act like what it models

12

Length (and tool)

measures how long something is
(ruler)

13

Mass (and tool)

measures how heavy something is
(triple beam balance)

14

Volume (and tool)

measures the amount of space something takes up
(graduated cylinder)

15

Temperature (and tool)

measures how hot or cold something is
(thermometer)

16

Density (and tool)

measures how dense something is (hydrometer)

17

Matter

anything that is a solid, liquid, or gas and takes up space

18

Physical Changes

a change of matter from one form to another without a change in chemical properties

19

Chemical Changes

a change in matter that turns into a different substance

20

Characteristic Properties

properties most useful in identifying a substance

21

Reactivity

how two or more substances combine to create one or more new substances

22

Thermal Conductivity

the rate at which a substance transfers heat

23

Explain the rule used to decide what is or is not matter.

It has to be a sold, liquid, or gas and it has to be made of atoms

24

Explain the molecular difference between the three states of matter.

solids - the atoms are very close together and retains its shape
liquids - the atoms are moderately spaced and it takes the form of its container
gas - the atoms are far apart and are moving quickly and will take the shape of its container

25

Discuss why the mercury in a thermometer rises when heated.

The molecules expand which also expands the actual mercury.

26

Contrast chemical and physical changes.

chemical - a change that affects the object on a chemical level and sometimes changes the substance
physical - a change that affects the object on a physical level and sometimes changes the object's appearance

27

Tell why scientists use characteristic properties to identify substances.

because they are the same for each substance;
ex: a large chunk of iron has the same characteristic properties as a tiny piece of iron

28

***Be able to analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.***

PRACTICE!

29

Atom

smallest unit of matter; made up of proton, neutrons, and electrons

30

Isotopes

an atom with a different amount of neutrons than normal

31

Atomic Number

the number of protons in an atom

32

Atomic Mass

the number of both protons and neutrons

33

Ions

an atom with a different amount of protons or electrons than normal

34

Ionic Board

M to NM / a bond in which atoms transfer electrons

35

Covalent Bond

NM to NM / a bond in which atoms share electrons

36

Reactants

participants in a chemical reaction

37

Products

created in a chemical reaction

38

Law of Conservation of Mass

states that mass is neither created nor destroyed

39

List 5 things that describe an atom.

1. composed of protons, neutrons, and electrons
2. always moving
3. mostly empty space
4. very small
5. has mass

40

How can you use the periodic table to identify protons, neutrons, and electrons in an atom?

P = Atomic Number
E = Same as P
Neutron = Atomic Mass-Atomic Number

41

Discuss the rules for creating isotopes.

isotopes = uneven amount of neutrons
ions = uneven amount of protons and electrons

42

How can you use the periodic table to determine the number of electron shells and valence electrons for atoms?

groups and periods:
periods = vertical
groups = horizontal

43

Contrast an ionic bond with a covalent bond. Determine if a molecule/compound is formed by an ionic or covalent bond.

ionic = electrons giving to another atom
covalent = electrons being share with another atom
ionic = nonmetal ---> metal
covalent = nonmetal ---> nonmetal

44

Describe the relationship between the reactants and the products in a chemical reaction.

You start with reactants. When in contact, the reactants begin reacting to each other. This creates a new substance which is called the product.

45

Explain the law of conservation of mass as demonstrated in your lab experiences.

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction. For example, if you put two different reactive substances in a bag, weigh them, and get 120 grams. Then you mix them together and weigh them after the reaction, it still weighs 120 grams.

46

Energy

the ability to do work

47

Kinetic Energy

energy of motion

48

Potential Energy

energy an object has due to its position

49

Mechanical Energy

the sum of PE and KE

50

Thermal Energy

heat energy due to the random motion of particles

51

Chemical Energy

energy of a compound that changes as its atoms are rearranged

52

Electrical Energy

energy of moving electrons

53

Light Energy

energy produced by the vibrations of electrically charged particles

54

Nuclear Energy

energy produced from the changes in the nucleus of an atom

55

Energy Conservation

the act of changing one type of energy to another

56

Law of Conservation of Energy

a law that states that energy cannot be created or destroyed, but can change from one form to another

57

Contrast kinetic and potential energy.

kinetic = energy of movement/highest at high speeds
potential = energy of an object from its position that could become kinetic/highest at high altitudes

58

Identify the factors that affect the amount of potential and kinetic energy.

speed = kinetic
height = potential
friction = reduces both

59

Explain the relationship between kinetic, potential, and mechanical energy.

NO ANSWER

60

Describe the energy conversions that take place on a roller coaster, and explain how energy is conserved.

potential ---> kinetic (going downhill)
kinetic ---> potential (going uphill)
electric ---> kinetic (turning wheels to move uphill)
The amount of mechanical energy is always the same, never created or destroyed, so energy is conserved.

61

Give three examples of one form of energy being converted into another form.

electric ---> light (flashlight)
chemical ---> kinetic (walking or running)
electric ---> sound (radio)

62

Explain the Law of Conservation of Energy.

States that energy can neither be created nor destroyed.

Example:
person going downhill
p=100 k=250 350
person near top of hill
p=300 k=50 350
It stays the same.

63

Open Response/Short Answer
Support a claim, using evidence, that when kinetic energy of an object changes, energy is transferred to or from the object.

**PRACTICE WRITING THIS.**
Three parts:
A - answer the question
B - draw a model and label
C - total amount of energy