Chemistry Flashcards
(114 cards)
1
Q
Definition of Matter
A
has mass; takes up space
2
Q
States of Matter
A
Solid, Liquid, Gas, Plasma
3
Q
Solid
A
- definite shape
- definite volume
- molecules move slowly (vibrate)
4
Q
Liquid
A
- indefinite shape
* definite volume
5
Q
Gas
A
- indefinite shape
* indefinite volume
6
Q
Plasma
A
- indefinite shape
- indefinite volume
- molecules move really fast
- electrically-charged particles
7
Q
Definition of Shape
A
a particular form
8
Q
Definition of Volume
A
amount of space an object occupies (takes up)
9
Q
Definition of Mass
A
amount of matter in an object
10
Q
Kinetic Theory of Matter
A
the theory that all matter is made up of tiny particles that are in constant motion
11
Q
Thermal Expansion
A
a characteristic of matter causing it to expand when heated and contract when cooled
12
Q
What are particles like in a solid?
A
- very close together
* vibrate in position
13
Q
What are particles like in a liquid?
A
- close together
* move over each other
14
Q
What are particles like in a gas?
A
- seperate from one another
* move in all directions
15
Q
What are particles like in a plasma?
A
- seperate from one another
- move in all directions
- gas-like
16
Q
What are Crystalline Solids?
A
solids whose particles are arranged in repeating geometric patterns called crystals (most solids)
17
Q
Examples of Crystalline Solids
A
Rock, Tree
18
Q
What are Amorphous Solids?
A
solids that are not made out of crystals (they slowly change shape)
19
Q
Examples of Amorphous Solids
A
Wax, Play-Doh
20
Q
What do liquids do in a container?
A
they take the shape of the container
21
Q
Examples of Liquids
A
Milk, Soda
22
Q
What does a gas do in available space?
A
it expands and contracts to fill the available space
23
Q
Examples of a Gas
A
Carbon Dioxide, Helium in a tank
24
Q
What is the most common form of matter in the universe?
A
Plasma
25
What is most of our solar system's mass composed of?
99% of our solar system's mass is composed of the sun
26
Because of extremely high temperatures, particles in plasma do what?
move more rapidly, collide, and break into smaller charged particles
27
Examples of Plasma
Stars (i.e. The Sun), lightning, fire
28
Going from a Solid to a Liquid is called...
melting
29
Going from a Liquid to a Solid is called...
freezing
30
Going from a Gas to a Liquid is called...
condensation
31
Going from a Liquid to a Gas is called...
evaporation
32
Going from a Solid to a Gas is called...
sublimation
33
What is Evaporation?
change of a substance from a liquid state to a gaseous state
34
example of Evaporation
a puddle disappears on a sunny day
35
What is Condensation?
change of a substance from a gaseous state to a liquid state
36
example of Condensation
water on the outside of a cold glass
37
What is Sublimation?
a type of evaporation in which a solid changes directly to a gas without going through a liquid state
38
example of Sublimation
dry ice
39
What is a Change of State?
the conversion of a substance from one physical form to another
40
What is the difference between Endothermic Changes and Exothermic Changes?
energy is added during endothermic changes. energy is removed during exothermic changes.
41
The Freezing Point and Boiling Point of a substance...
are the same temperature
42
What do both Boiling and Evaporation result in?
a liquid changing to a gas
43
Condensation is...
the change of a gas to a liquid // the reverse of evaporation
44
What does Sublimation do?
Sublimation changes a solid directly to a gas
45
During a Change of State, what does the temperature of a substance do?
nothing; the temperature if a substance does not change during a change of state
46
What are Physical Properties?
a characteristic of matter that can be observed or measured WITHOUT CHANGING the identity of the matter
47
examples of Physical Properties
length, mass, volume, density, odor, color, state of matter, flexibility, texture, shape, magnetic
48
What are Chemical Properties?
a characteristic of matter that describes its ABILITY TO CHANGE into NEW MATTER with DIFFERENT properties
49
examples of Chemical Properties
flammability, reactivity (can react with another substance to form something new), potential to rust and/or rot
50
What is a Physical Change?
a change of matter from one form to another that affects one or more physical properties
51
What is a Chemical Change?
a change that occurs when one or more substances change into new substances with different properties
52
It could be a physical change if the substance...
1. Changes shape
2. Dissolves
3. Changes State/Phase
4. Changes color
53
What makes something a physical change?
No matter what, the substance is still the same
54
It could be a chemical change if a substance...
1. Changes color because of a chemical reaction
2. Gives off gas/bubbles (forcefully)
3. Burns
4. Forms a new substance
5. Gives off heat
6. Feels cold
55
What is an Exothermic Reaction vs. an Endothermic Reaction?
exothermic reaction - substance gives off heat
| endothermic reaction - substance feels cold
56
What is an example of the physical property Solubility?
a flavored drink mix DISSOLVES in water
57
What is an example of the physical property Thermal Conductivity?
plastic foam protects you from hot liquid
58
What is an example of the physical property Malleability?
aluminum can be FLATTENED into sheets of foil
59
What is an example of the physical property Ductility?
copper can be PULLED INTO THIN WIRES
60
What is an example of the physical property Odor?
an onion gives off a very distinctive SMELL
61
What is an example of the physical property Density?
a golf ball has MORE MASS than a table tennis ball, but the VOLUMES ARE SIMILAR
62
When a substance undergoes a physical change, what is not changed? What is changed?
its composition does not change. only a physical property is changed.
63
The chemical property that describes the ability of 2 or more substances to combine to form new substances is called...
reactivity
64
The ability of a substance to burn is a chemical property known as...
flammability
65
An iron nail is reactive with...
oxygen in the air (reaction: rust)
66
What is a Characteristic Property of matter?
either a physical or chemical property that scientists use to help identify & classify matter
67
Does a substance always have chemical properties?
yes, even though they are difficult to observe
68
How do you know that baking a cake involves chemical changes?
Baking a cake involves chemical changes because the cake's properties differ from the properties of the ingredients before they were baked.
69
Why are chemical changes hard to reverse?
because they change the identity of the substances involved
70
What is the most important question to ask to determine whether a change is physical or chemical?
Did the composition change? (chemical ~ yes; physical ~ no)
71
What is the name of the process by which water is broken down into hydrogen and oxygen using an electric current?
electrolysis
72
What are Elements?
They're pure substances made of only 1 kind of atom.
73
What are Atoms?
They're tiny structures found in all matter.
74
What do most substances contain?
many different atoms. only the elements contain only 1 kind of atom
75
Elements:
1. One kind of atom
2. Pure
3. Seperated in nuclear reactions
76
Compounds:
1. 2 or more kinds of atoms chemically bonded
2. Pure
3. Seperated in chemical reactions
77
Mixtures:
1. 2 or more elements or compounds physically together
2. Not pure
3. Seperated in physical reactions
78
A substance that cannot be seperated into simpler substances by physical or chemical means is...
an element
79
What do elements contain only 1 of?
contains only 1 type of atom
80
Where can elements be found?
on the periodic table
81
What are the 3 major categories of elements?
metals, nonmetals, and metalloids
82
examples of elements:
Helium, Iron, Calcium
83
A subtance made of 2 or more elements that are chemically combined is...
a compound
84
What does a compound have a specific ratio of?
a specific ratio of elements (formula)
85
How do the properties of the compound compare to the elements it's made from?
properties of the compound are different than the individual elements it's made from
86
examples of compounds:
Table Salt -> Sodium & Chlorine: NaCl
Sugar (sucrose) -> Carbon, Hydrogen, & Oxygen: C H O
12 11
87
A combination of 2 or more substances not chemically combined is...
a mixture
88
Do the properties of substances change when forming a mixture?
no; no change in original properties of substances
89
Is there a specific ratio of substances when forming a mixture?
no; formed by using any ratio of substances (# of choc. chips in a cookie doesn't matter; it's still a choc. chip cookie)
90
examples of mixtures:
Hot Chocolate, Bowl of Cereal, Salt Water
91
This represents the element. While te English name sometimes matches, the Latin name was sometimes used to create this.
Element Symbol
92
This is the most commonly used word for the element.
Element Name
93
Designated by the number of protons in the nucleus, this determines hotizontal placement on the table.
Atomic Number
94
This is determined by the weight of an atom.
Atomic Mass
95
```
LABEL THE PARTS:
6
C
Carbon
12.01115
```
1. Atomic Number
2. Element Symbol
3. Element Name
5. Atomic Mass
96
Periodic Table of Elements:
the arrangement of elements according to repeating changes in properties
97
How are elements arranged?
Elements are arranged in order of their ATOMIC NUMBER - not atomic weight
98
What are vertical columns called, and what do elements in each vertical column have in common?
Vertical columns are called groups or families. There are 18 groups. Elements in each group or family have similar properties.
99
What determines element's properties?
Similar electron arrangements determine element's properties. The number of electrons in the outer energy level determines the chemical properties of that element.
100
What are horizontal rows of elements called?
Horizontal rows if elements are called periods.
101
Where are elements that are METALS placed on the periodic table?
All elements to the LEFT of the stair step line are METALS (except hydrogen)
102
What are common properties of metals?
metals are commonly solid at room temperature, shiny, and good conductors of heat & electricity
103
Where are elements that are NONMETALS placed on the periodic table?
All elements to the RIGHT of the stair step line are NONMETALS
104
What are common properties of nonmetals?
Nonmetals are commonly gases or brittle solids at room temperature, and most do not conduct heat & electricity well
105
Where are elements that are METALLOIDS placed on the periodic table?
All elements NEXT TO the stair step line are METALLOIDS
106
What properties do metalloids have?
Metalloids have properties of both metals & nonmetals
107
What elements are TRANSITION ELEMENTS?
All elements in GROUPS 3-12 are TRANSITION ELEMENTS
108
What are transition elements?
Transition elements transition from very metallic to nonmetallic properties
109
Why are elements in group 18 called the noble gases?
They don't react with other elements.
110
What does it mean if an element is synthetic?
It means the element is manmade.
111
Separation of Mixtures:
| Evaporation
a mixture is heated until the water changes from a liquid to a gas. the water vapor can be collected & condensed back into liquid form. the reamainin substance has then been separated from the water.
112
Separation of Mixtures:
| Sifting/Filtering
a mixture is passed through a screen that separates large particles from small particles. the smaller particles pass through while the larger particles are collected on the screen.
113
Separation of Mixtures:
| Weight
a special machine called a centrifuge spins a mixture to separate substances with different masses. the heavier substance is forced to the bottom & the liquid is siphoned off.
114
Separation of Mixtures:
| Magnetism
a magnet is used to separate magnetic materials from those that are not magnetic.
