Chemistry: Quiz 1 Flashcards
(62 cards)
1
Q
Particle Model of Matter
A
All matter is made up of small particles called atoms
The particles in a substance are attracted to each other
All particles in a pure substance are the same
There are spaces between particles
Particles are always moving
2
Q
Mass
A
Matter is anything that has mass and occupies space
3
Q
Solids
A
Particles are tightly packed
Fixed (definite) volume and shape
Particles move very little
4
Q
Liquids
A
Particles are farther apart than in a solid
Fixed (definite) volume and changing shape
Particles move around
5
Q
Gases
A
Particles are loosely packed
Changing volume and shape
Particles move freely (need a lid for containers)
6
Q
What are the different ways matter can change state
A
Solid → liquid: melting
Liquid → solid: freezing
Liquid → gas: vapourizing / evaporating
Gas → liquid: condensing
Solid → gas: subliming
Gas → solid: subliming
7
Q
Physical Properties
A
- Can be observed with the five senses
Ex: shape, size, texture, flexibility, boiling point, melting point, state, how hard it is, magnetic, density - When a physical change occurs, the molecules do NOT change
8
Q
Chemical Properties
A
- Describes the reactivity of a substance
- How a substance will react to other substances
- A chemical change occurs when you create a new substance
Ex: changes in smell or colour, how easily it catches fire or burns, how it reacts with other substances.
9
Q
Pure Substance
A
- All parts that make up the substance are identical
- Its chemical and physical properties are constant
10
Q
Elements (from the chart)
A
- It is a substance made up of only one type of atom
- Cannot be broken down into other substances
11
Q
Compounds
A
- A chemical combination of two or more elements in a specific ratio
- Elements are held together by chemical bonds
12
Q
Homogenous
A
A mixture in which the different substances are NOT visible
12
Q
Colloid
A
A mixture in which the suspended substance cannot be separated from the other substances in the mixture
13
Q
Mixture
A
- A combination of pure substances
- The proportions in a mixture vary, so the properties of the mixture vary
14
Q
Heterogeneous
A
A mixture in which the different substances are visible
15
Q
Suspensions
A
A mixture in which the components are in different states
16
Q
Mechanical Mixture
A
A mixture in which the different substances are visible
17
Q
John Dalton
A
- All matter is made up of small, invisible particles called atoms
- Described atoms as tiny spheres
- All atoms of an element have identical properties such as size and mass
- Atoms of different elements have different properties
- Atoms of different elements can combine to form now substances (compounds)
18
Q
J.J. Thomson
A
- Discovered the electron (negative)
- Atom was represented using the “plum pudding” or “raisin bun” model
- His experiments showed that atoms of different elements contained smaller particles that were identical
19
Q
Ernest Rutherford
A
- Discovered the nucleus of the atom
- Believed that most of the atom was empty space
- The nucleus of the atom contained protons (positive) and neutrons (neutral)
- The electrons orbited around the nucleus
20
Q
Niels Bohr
A
Electrons travel only in specific electron shells or energy levels
21
Q
Current Atomic Theories
A
- Each level can be thought of as a cloud of negatively charged electrons
- The electron cloud surrounds a nucleus containing two types of particles (neutrons and protons)
- Electrons are grouped in pairs
22
Q
Elements
A
- Substances that cannot be broken down into other substances
- The basic building blocks of all materials
- 90 elements are naturally occuring, others are synthetic (created by humans using nuclear reactors, particle accelerators, or the atomic bomb
23
Q
Atomic Number
A
- Number that indicates the amount of protons in a particular element
- The atomic number defines what the element is
24
Group (Families)
- The vertical columns on the periodic table
- There are 18 groups
- Groups have similar chemical and physical properties
25
Periods
- The horizontal rows on the periodic table
- There are 7 periods
- Each period has the same number of energy levels
26
Properties
- Elements have certain properties / characteristics depending on whether they are a metal, non-metal or metalloid
- Metals are on the left of the staircase
- Non-metals are on the right
- Metal are along the staircase
27
Properties of Metals
- Solid at room temperature (1 exemption: mercury)
- Good conductors of heat and electricity
- Shiny in appearance; can be polished
- Malleable: can be hammered or rolled into thin sheets
- Ductile: they can be stretched into a wire
28
Properties of Non-Metal
- Can be solid, liquid, or gas at room temperature
- Poor conductors of heat and electricity
- Dull in appearance
- Brittle: breaks when hammered
- Not ductile
29
Metalloids
Share some properties of both metals and nonmetals
30
Alkali Metals
- Metals in the first column or group 1
- With the exception of francium, these metals are very soft and shiny and silvery
- These elements react vigorously, event violently, with water and must be stored in oil to prevent contact with the moisture in the air
31
Alkaline - Earth Metals
Metals in the second column of group 2
These elements are shiny, silver but not as soft as the alkali metals
Their compounds tend to be white
32
Halogens
- The reactive nonmetals in group 17 of the periodic table
- These elements are so reactive that they are never found as elements in nature
33
Noble Gases
- Elements belonging to group 18
- These elements are very unreactive
34
Subatomic Particles
- Protons
- Neutrons
- Electrons
35
Atomic Mass
- The mass of an average atom of the element
- The total number of protons and neutrons
- Protons and neutrons gather together in the nucleus of the atom
- This number may be slightly different depending on which periodic table you are looking at.
36
Calculating th emost common number of neutrons in an atom
- Atomic mass on the periodic table is the most common (average) mass of one atom of that element (they can vary)
- The number of protons never changes and is the same as the atomic number
Number of neutrons = atomic mass - atomic number
37
Isotopes
Since the number of neutrons can vary, atoms of the same substance with different numbers of neutrons are called isotopes
38
Charge
- Atoms have no net charge
- The number of protons = the number of electrons
- The atomic number tells you how many electrons and protons are in an atom
39
Electron Clould
- Space in which electrons orbit the nucleus at high speed
- Within the clouds are energy levels
40
Energy Levels
- Areas where electrons orbit the nucleus
- Each level can fit a certain number of electrons (octet rule)
41
Valence Electron
Electrons in the outer energy level are known as valence electrons. Elements in the same group have the same number of valence electrons.
42
Ions
- Atoms want to have a stable (full) outer energy level
- To become stable the atoms will gain or lose (whichever is easiest) valence electrons to ensure their outer level is full
- These electrons are transferred to other ions (forming compounds)
- Gain or loss of electrons causes the atom to have a charge
43
Positive Ions
- When an ion loses electrons it becomes positively charged
- All metals are
positively charged
- Positively charged ions
are called cations (cats
have paws)
44
Negative Ions
- When an ion gains electrons it becomes negatively charged
- All non-metals are
negatively charged
- Negatively charged
ions are called anions
45
The International Union of Pure and Applied Chemistry (IUPAC)
The group responsible for naming compound
46
Molecular Compounds
- Are formed when 2 or more nonmetals share electrons in their outer energy level to become stable
- The bonds formed when electrons are shared are called covalent bonds
- The bond formed is not as strong as an ionic bond
47
Molecular Elements
- Form molecules made up of only one type of atom
- Have the same name as the element
- The special seven
48
The Special Seven
- These seven elements form diatomic molecules when they are individually writing (H2, N2, O2, F2, Cl2, Br2, I2)
- Two other polyatomic molecules are sulphur (S8) and phosphorous (P4)
49
Ionic Compounds
- Formed when electrons are transferred from a metal to a non-metal
- Creates an ionic bond between a cation (positive ion) and an anion (negative ion)
- Cations donate electrons to anions as they form a molecule
- The ratio of positive charges to negative charges must be zero
50
Polyatomic Ions
- Ions made up of a group of atoms acting as ONE UNIT
- Held together with covalent bonds
51
Multivalent Elevents
- Multivalent elements form ions that can have more than charge
- They are listed on the periodic table for you
- The first charge listed in the most common
52
Water
H2O
53
Hydrogen Peroxide
H2O2
54
Ammonia
NH3
55
Sucrose
C6H12O11
56
Glucose
C6H12O6
57
Methane
CH4
58
Propane
C3H8
59
Methanol
CH3OH
60
Ethanol
C2H5OH
61
Hydrogen Sulfide
H2S
