Unit A: Exam Flashcards
1
Q
What does an orange diamond mean?
A
Warning
2
Q
What does a red octagon mean?
A
Danger
3
Q
What does a yellow triangle mean?
A
Caution
4
Q
What shape are WHMIS symbols in?
A
Circles
5
Q
What does WHMIS stand for?
A
Workplace Hazardous Materials Information System
6
Q
What are MSDS?
A
Sheets that identify the chemical and physical hazards associate with each substance. It also includes the physical properties
7
Q
What is the most important safety feature in the lab?
A
You
8
Q
Why does the Canadian government have so many rules and regulations for chemicals?
A
The environment
9
Q
What do are physical properties?
A
Properties that describe the physical appearance and composition of a substance
10
Q
What are some examples of physical properties?
A
- Boiling point
- Melting point
- Freezing point
- Malleability
- Ductility
- Color
- State
- Solubility
- Crystal formation
- Conductivity
- Magnetism
11
Q
What is Malleability?
A
The ability to be beaten or rolled into sheets without crumbling
12
Q
What is Ductility?
A
Ability to be stretched without breaking
13
Q
What is Solubility?
A
The ability to dissolve
14
Q
What is Conductivity?
A
Ability to conduct heat or electricity
15
Q
What is Magnetism?
A
Magnetic attraction between objects
16
Q
What are Chemical Properties?
A
Properties that describe the reactivity of a substance
17
Q
What are some examples of chemical properties?
A
- Ability to burn
- Flash point
- Behavior in air
- Reaction with water
- Reaction with acids
- Reaction to heat
- Reaction to litmus paper
18
Q
What is Flash Point?
A
Temperature needed to ignite a flame
19
Q
What are the 2 groups that matter can be classified into?
A
Pure substance and mixtures
20
Q
What is a pure substance?
A
A pure substance is when all the particles that make it up are identical and cannot be broken down
21
Q
What can be in a pure substance?
A
An element or compound
22
Q
What is a compound?
A
A chemical combination of two or more elements in a specific ratio
23
Q
What is a mixture?
A
A combination of pure substances. The proportions and properties vary
24
Q
What are the 3 types of heterogeneous mixtures?
A
- Mechanical mixtures
- Suspensions
- Colloids
25
What is the one type of homogenous mixture?
Solution
26
What are the 4 types of mixtures?
- Solutions
- Mechanical mixtures
- Suspensions
- Colloids
27
What is a mechanical mixture?
A mixture where the different parts are visible such as soil
28
What is a suspension?
A type of mixture where the components are in different states such as mud
29
What is a colloid?
A type of mixture where the suspended mixture is in different states but cannot separate out easiliy
30
What is solution?
When the different parts are not visible and the mixture is uniform throughout
31
What is a chemical reaction?
A process that occurs when a substance or substances react to create a different substance or substances
32
What do chemical reactions always produce?
New substances that have completely new properties
33
What are the characteristics of chemical reactions?
- Involve production of new substance
- Involve the flow of energy
- Cause a phase change
34
What is a phase change?
-Formation of a gas or solid
35
What are the ways of food preservation?
- Freezing
- Salting
- Fermentation
36
What does heating do to food?
Temporarily sterilizes it
37
What is sterilization?
Any process that kill micro-organisms
38
What does freezing to food?
Preserves food almost indefinitely
39
How does freezing preserve food?
The low temperature prevents the growth of micro-organisms that cause decay
40
What salting do to meat and fish?
Dries and preserves by drawing the water out and kills bacteria
41
What caused scurvy?
The lack of vitamin C
42
What did sea captains do to get rid of scurvy?
They brought pickled cabbage aka Sauerkraut
43
What is fermentation?
A technique using the bacteria lactobacilli that converts starches and sugars into a chemical called lactic acid
44
What is Lactic Acid?
A preservative that prevents that prevents the growth of bacteria that cause food to rot
45
How is lactobacilli beneficial to food?
Increases digestion and increase vitamin levels
46
What is smoking?
A method of food preservation
47
How does smoking preserve foods?
Introduces anti-oxidants that slow the rotting process
48
What is metallurgy?
The science of producing and using metals
49
Why was gold used extensively in jewelry?
Because it is soft and easy to work with
50
What was copper originally used for?
Weapons and jewelry
51
What type of copper did the intuit use?
Native copper found in pure form in the Coppermite river
52
What was the problem with copper?
When it was hammered it became bitter
53
What is annealing?
Heating of a metal before it is hammered
54
What solved the copper problem?
Annealing and smelting
55
What is smelting?
Separating a metal from other elements in a compound by heating
56
What is bronze?
The product produced when tin and copper are smelted
57
What is steel?
The product produces when Iron and Carbon are mixed
58
What did Aristotle believe about matter?
That it was made from fire, earth, water and air
59
Who was the first to coin the term atoms?
Democratis
60
What is alchemy?
A combination of science and magic
61
Why was scientific knowledge slow to develop in alchemy?
Because they were just finding ways to get rich quickly and did not want to share information
62
What did Robert Boyle do?
Measured relationships between volume and pressure of gasses
63
Who created the Law of Conservation of Matter?
Antoine Lavoisier
64
Who were the 4 scientists who contributed to models of atoms?
- Dalton
- Thomson
- Rutherford
- Bohr
65
Who created the Billiard ball model?
John Dalton
66
Describe John Daltons model of the atom
- All elements of a certain element are identical
- Atoms of different elements have different properties
- Atoms can combine in fixed rations to form substances
- Small spheres
67
Who discovered the electron?
J.J. Thomson
68
How did J.J. Thomson discover the electron?
- He was experimenting with beams of particles in a vacuum.
- It showed that all the beams were negative
- He concluded that they all must have something in common causing them to be negative
69
What model of the atom did J.J. Thomson create?
The raisin bun model
| -He suggested that the sphere was positive and it had negative electrons embedded in it
70
What did Ernest Rutherford believe about atoms?
An atom is mainly empty space but each atom has a tiny positively charged core
71
How did Ernest Rutherford come to the conclusion of the nucleus?
- He had a radioactive material that produced positive particles and aimed it at gold foil
- He thought they would go straight through or be slightly deflected but instead some bounced back
- He said that sometimes the positive core was so strong it caused the atom to be very deflected
72
Who discovered the nucleus?
Rutherford
73
What did Neils Bohr believe?
Electrons orbited the nucleus in different levels
74
How did Neils Bohr come to his conclusion?
When electrons fall from different energy levels they emit different light
75
What is the Quantum Mechanics Model of atoms?
Electrons are thought of as clouds of negative charge that surrounds a nucleus of protons and neutrons
76
What are reactants?
The substances that react in a chemical reaction
77
What are products?
The new substances produced in a chemical reaction
78
How many elements are there?
115
79
What are the 3 classes of the periodic table?
Metals
Non-metals
Metalloids
80
What are the physical characteristics of metals?
- Silver or grey
- Shiny
- Malleable and ductile
- Solid
81
Which metal is not solid at room temperature?
Mercury
82
What does inert mean?
Unreactive
83
Why are non-metals grouped together?
For their lack of resemblance to each other
84
What type of variation is there in non-metals?
State
Color
Reactivity
85
Which group on the periodic table is the most non-reactive?
Noble gasses
86
What are molecules?
Groups of non-metallic elements held together by covalent bonds
87
What are metalloids?
Elements that have properties that are intermediate between metals and non-metals
88
What properties does the periodic table organize elements?
Chemical
89
Why is hydrogen special?
It is a non-metal but acts like a metal in chemical reactions
90
What is a period?
Each horizontal row on the periodic table
91
What is a group or family?
Each vertical column on the periodic table
92
What are chemical families?
Groups of elements that have similar chemical and physical properties
93
What is the very first group in the periodic table called?
Alkali metals
94
What is the group to the left of the noble gases?
Halogens
95
Which two groups in the periodic table react to form salts?
Halogens and alkali metals
96
What is an atom?
The smallest part of the element that still has the properties of the elements
97
What are the 3 kinds of subatomic particles?
Electrons
Protons
Neutron
98
What are electrons?
Negatively charged particles
99
What are protons?
Positively charged particles
100
What are neutrons?
Neutral particles
101
What adds most weight in an atom?
Protons
102
What is an energy level?
A region of space near the nucleus that may be empty or contain electrons
103
How many electrons can each energy level hold?
2, 8, 8
104
What does the atomic number indicate?
The number or protons on an atom
105
What are isotopes?
Atoms of the same element that contain different numbers of neutrons
106
What is Deuterium?
An isotope of hydrogen that contains 1 proton and neutron
107
What is the mass number?
Total number of protons and neutrons in the nucleus of an atom
108
What will the element of an isotope look like?
Mass Number
Element Symbol
Atomic Number
109
What is the atomic molar mass?
The average mass of an elements isotopes
110
What is ionization?
The process of gaining or losing an electron
111
What is an ion?
An electrically charged atom
112
What are cations?
Positively charged ions
113
How is a cation formed?
An atom loses an electron and represents with a +
114
What are anions?
Negatively charged ions
115
How do anions form?
When atoms gain electrons and represents a -
116
Why do atoms gain or lose electrons?
So they have the same number of electrons of a noble gas
117
Why are noble gasses so stable?
They have filled outer energy levels
118
What are electrons in the outermost energy level called?
Valence electrons
119
What is the valence number?
The number of electrons an element can gain or lose to combine with other elements
120
What does the octet rule state?
Atoms bond in such a way as to have 8 electrons in their valence energy level
121
What is a crystal lattice?
What forms when an ionic compound forms
122
What state are the physical properties of ionic compounds?
- Solid
- High melting and boiling points
- Conductive
- Retention of crystal shape
123
What are multivalent elements?
Elements with more than 1 stable element
124
What is the chemical formula for methane?
CH4
125
What are the physical properties of molecular compounds?
- Any state
- Poor conductors
- Low boiling and melting points
126
How do atoms of molecules bond?
Using covalent bonds
127
What is a covalent bond?
When atoms share electrons so that they exist in both elements at the same time
128
What are molecular elements?
Molecules made of only type of element
129
What are prefixes for numbers 1-10
```
Mono
Di
Tri
Tetra
Penta
Hexa
Hepta
Octa
Ennea
Deca
```
130
How can you recognize an ionic compound?
They will always have a positive and negative ion
131
What does polar mean?
Each water molecule is slightly positive and slightly negative so they attract each other
132
What is an electrolyte?
Any solution that conducts electricity
133
What does the subscript aq mean?
Aqueous, dissolved in water
134
What is a precipitate?
A solid with a low solubility that forms when 2 solutions are mixed
135
What is special about water?
It is polar because it has a positive and negative end so that they attract each other
136
Why does ice float?
Because there are fewer molecules of water in the ice because it spreads out
137
What type of acid is in stomachs?
Hydrochloric acid
138
What is an acid?
A compound that dissolves to form a solution with a pH lower than 7
139
What is a base?
A compound that dissolves to form a solution with a pH higher than 7
140
What is the pH of saliva?
Basic
141
What does the enzyme pepsin do?
Speeds up the digestion of protein and amino acids
142
What does the pancreas do?
Produces sodium hydrogen carbonate to deactivate pepsin
143
What is a buffer?
A substance that can keep the pH of a solution nearly constant despite the addition of an acid or base
144
What are the properties of acids?
- Sour
- Not slippery
- Reactive with metal
145
What are the properties of bases?
- Bitter
- Slippery
- Non-reactive with metal
146
What is a universal indicator?
A mixture of several different indicators that change color as the acidity changes
147
What is the pH of a neutral substance?
7
148
How can you identify an acid by its chemical formula?
It will begin with H or end with -COOH and will always be aqueous
149
How can you identify a base by its formula?
It will always end in OH
150
What is neutralization?
A reaction between acids and bases that produces water and salt
151
What are Chlorofluorocarbons?
Chemicals that chlorine that act as catalysts in the upper atmosphere and causes destruction of the earths ozone layer
152
What are the 2 most commonly used hazardous recreational substances?
Alcohol and nicotine
153
How does alcohol affect the body?
Cause destruction of the liver, kidneys, and brain cells
154
What is physical dependence or addiction?
When the body becomes used to the drug and needs it to function
155
What is psychological dependence?
When the use of a drug is linked to a certain mood or feelings but when the drug wears off the feeling disappears
156
What is nicotine present in?
All tobacco products
157
Why are cigarettes dangerous?
Because they contain many chemical like carbon monoxide, tar, formaldehyde, and benzene. It also damages the respiratory or circulatory systems
