All sections Flashcards
(120 cards)
1
Q
Describe safety hazard symbols.
A
Indicates a degree and the type of hazard shown by a symbol inside the border.
Degrees
yellow triangle: caution
orange diamond: warning
red octagon: danger
2
Q
What is WHMIS?
* review the symbols
A
Workplace hazardous materials information system; they’re warning symbols of hazardous materials.
3
Q
What is MSDS?
A
Material Safety data Sheet; identifies the chemical and physical hazards associated with each substance. it includes physical data, such as melting point and boiling point, toxicity, health effects, first aid, and spill/leak cleanup procedures.
4
Q
What are physical properties? Name 10 of them.
A
Physical properties describe the physical appearance and composition of a substance.
Examples: boiling/condensation point, melting/freezing point, malleability, ductility, colour, state, solubility, crystal formation, conductivity, magnetism
5
Q
What is malleability?
A
The ability to be beaten or rolled into sheets without crumbling.
6
Q
What is ductility?
A
The ability to be stretched without breaking.
7
Q
What is solubility? Crystal formation? What about conductivity?
A
Solubility is the ability to dissolve. Crystal formation refers to crystalline appearance. Conductivity is the ability to conduct heat or electricity.
8
Q
What is a chemical property? Name 7.
A
They describe the reactivity of a substance.
Examples: ability to burn, flash point, behaviour in air, reaction with water, reaction with acids, reaction with acids, reaction heat, reaction to red/blue litmus.
9
Q
What is flash point?
A
The temperature needed to ignite a flame.
10
Q
What is a pure substance?
A
All the particles that make up the substance are identical; it cannot be broken down into other substances and is made up of one type of atom. It may be an element or a compound.
11
Q
What is a mixture?
A
A combination of pure substances; includes mechanical mixtures, suspensions, colloids, and solutions.
12
Q
What is a mechanical mixture?
A
Mixture in which the different substances are visible.
13
Q
What is a heterogeneous mixture?
A
Mixture in which the different substances are visible.
14
Q
What is a suspension?
A
It is a kind of mechanical mixture where the components are in different states. E.g. mud is a suspension of dirt in water.
15
Q
What is a colloid?
A
It is similar to a suspension but the suspended substance cannot be easily separated from the other substance.
16
Q
What is a solution?
A
One substance is dissolved in another.
17
Q
What is homogenous mixture?
A
The separate components are not visible.
18
Q
What is a chemical reaction?
A
It is a process that occurs when a substance(s) react to create a different substance or substances. They always involve the production of new substances with their own physical and chemical properties. Energy is always absorbed or released.
19
Q
Name 3 characteristics of a chemical reaction.
A
1) all reactions involve reactions involve the production of new substances with their own characteristics
2) all reactions involve a flow of energy (may be detected by a temp change)
3) many cause a phase change like the formation of a gas or a solid precipitate
Bonus: must be consistent with the law of conservation of mass.
20
Q
Describe a physical change.
A
- chemical components remain the same
- no new substances form
- e.g. freezing
21
Q
What is sterilization?
A
It is any process that kills micro-organisms.
22
Q
Describe heating and freezing. Are they a physical or chemical change?
A
Heating food (physically) temporarily sterilizes it. canning involves heat sterilization. Freezing is another physical process that can preserve food; the very low temperature prevents the growth of micro=organisms
23
Q
What is salting? Is it a physical or chemical change?
A
Salting is a physical method of preventing meat and fish and is a method of drying. The salt draws the water out of the meat.
24
Q
What is fermentation? Is it a physical or chemical change? Make sure to mention lactobacilli and lactic acid.
A
Fermentation is a process in which chemical change occurs. It’s a preservation technique involving the bacteria called lactobacilli, which are present on the surfaces of all living things. They convert starches/sugars present in fruits and veggies into a chemical called lactic acid, which is a preservative that prevents the growth of bacteria that makes food rot.
Extra: lactobacilli make food more digestible and increase vitamin levels.
25
How does smoking preserve food?
Smoking introduces chemicals called antioxidants that slow the rotting process.
26
What is metallurgy?
The science of producing and using metals.
27
What practical advantages does copper have over gold?
Although gold is easier to work with, copper is harder, so it can be made into tools and weapons, as well as jewelry.
28
What is annealing?
It is the heating of copper before it is hammered. It made the copper easier to hammer because it was no longer brittle.
29
What is smelting?
It is the process of separating a metal from the other elements in a compound my melting
30
What is an alloy?
Any mixture of metals. E.g. copper and tin form an alloy called bronze.
31
What was Aristotle's description of matter? Was it correct? What about Democritus?
Aristotle believed that all matter was composed of fire, earth, water, and air. He was incorrect. Democritus proposed that matter was made up of tiny particles that could not be divided into smaller pieces. He called them atomos (means indivisible). His theory was much closer to today's model, but Aristotle was well-respected and his idea was accepted for the next 2000 years.
32
What is alchemy?
Alchemy was a combination of science and magic, with the goal of turning cheap metals into gold. Scientists wanted to get rich quick, so they were secretive about their work, meaning that specific knowledge was slow to develop.
33
What did alchemy contribute to the development of chemistry and science?
- mercury was discovered
- procedures for making mineral acids (like hydrochloric acid) were developed
- improved lab equipment
- helped develop casts
34
What atomic model did John Dalton create? Name four points that he used to explain matter.
Billiard ball model
- all matter is made of small, indivisible particles called atoms
- all the atoms of an element are identical in properties, such as size and mass
- atoms of different elements have different properties
- atoms of different elements can combine in specific fixed ratios to form new substances
35
What atomic model did J.J. Thomson create? Explain some of his discoveries.
Raisin bun/plum pudding model
- Thomson discovered the electron (negatively charged)
- atoms of different elements contained smaller particles that were identical called subatomic particles
36
What atomic model did Ernest Rutherford create? Explain some of his discoveries.
Planetary/nuclear model
- discovered the nucleus of the atom
- suggested that an atom is mainly empty space through which the positive particles could pass, but each atom has a tiny, dense, positively charged core
37
Explain Rutherford's gold foil experiment.
He shot positively charged particles of a radioactive substance at a thin sheet of gold foil. He predicted that they would pass straight through the foil, which happened to most of the particles. However, some bounced back and some were sharply deflected.
38
What atomic model did Neils Bohr create? What were some of his discoveries?
Bohr model
- proposed that electrons surrounded the nucleus in specific energy levels
- electrons do not fall below the lowest energy level (never merge with the positively charged nucleus)
39
Describe the quantum mechanical model of the atom.
- each electron is thought of as a cloud of negative charge, instead of a tiny negative particle
- electrons occupy the whole space all at once at different energy levels
- cloud surrounds a nucleus containing two types of particles called nucleons: protons and neutrons
40
What are nucleons and their charges?
Protons: positive electrical charge
Neutrons: no electrical charge
41
Describe metals.
- most are silver/grey
- shiny
- good conductors
- malleable and ductile
- most are solids at room temperature
- some are highly reactive, some are inert expect with the most corrosive acids
42
What does inert mean?
Unreactice/inactive
43
Describe non-metals.
- 17 non metals
- can be any state at room temp
- variation in colour
- dull
- usually good insulators
- some are highly reactive and some are generally unreactive, like noble gases
- half exist as molecules
- brittle
44
Describe metalloids.
- properties of metals and non metals
- some conduct electricity, but not very well
- often brittle solids
45
What is the periodic table?
It organizes all the elements according to their chemical properties. Metals are on the left side/centre, non-metals on the right, and metalloids in between
46
What is a period on the periodic table?
A horizontal row, numbered 1 to 7. Usually, the period an element is in determines their number of electron levels.
47
What is a group/family of the periodic table? What are groups 1 and 2? What about 17 and 18? Describe each of them.
Each vertical column, numbered 1 to 18. Chemical families are groups of elements that have similar chemical/physical properties. Group 1 is called the alkali metals, which are soft, shiny, silver, and very reactive with water. Group 2 is the alkaline-earth metals. They are shiny/sliver but not as soft as group 1. Group 18 is the noble gases, which are very unreactive. The elements in group 17 are halogens, which are poisonous and form salts with group 1.
48
What accounts for most of the mass of the atom? What about the volume?
Protons and neutrons take up most of the mass. Electrons take up most of the volume.
49
Describe the energy levels of an atom.
- a region of space near a nucleus that may be empty or may contain electrons
- electrons nearest the nucleus have the lowest energy, electrons in the levels farther away from the nucleus have more energy
- closest level can only old 2 electrons
- the next two can hold 8
- energy levels can be empty, partly filled, or entirely filled
50
Describe the atomic number.
- indicates the number of protons per atom of an element
- elements are ordered by this number
51
What is the mass number of an element?
- and integer equal to the total number of protons and neutrons in the nucleus of the atom
- also equal to the atomic molar mass rounded to the nearest whole number
52
What are isotopes?
Atoms of the same element that contain different number of neutrons. They change the mass number. The atomic number will remain the same.
53
What is isotope notation?
the element symbol with the atomic number as a subscript on the bottom left, the mass number as a superscript on the top left
54
What is the atomic molar mass?
The number underneath the element symbol; it is the average of all of an element's isotopes
55
What is ionization?
The process of gaining or losing one or more of an element's outermost electrons. It results in the formation of a compound.
56
What is an ion?
An ion is an electrically charged atom or groups of atoms.
57
What is a cation?
A positively charged ion (a metal). Cations LOSE electrons during ionization and transfer them to another atom (an anion).
58
What is an anion?
A negatively charged ion (a non-metal). Anions GAIN electrons during ionization, from a cation.
59
Why do atoms gain/lose electrons?
They want to have the same number of electrons as the nearest noble gas, meaning their outermost energy level is full, making them more stable/less reactive.
60
What are valence electrons? What is valence? What is valence number?
Valence electrons are the electrons in the outermost energy level. Valence is the tendency to gain or lose electrons. Valence number is commonly used to describe the number of electrons an element can gain or lose to combine with other elements.
61
True or false: elements in the same family have the same number of valence electrons.
True
62
Describe the octet rule
63
What body/organization is responsible for naming compounds?
The International Union of Pure and and Applied Chemistry (IUPAC)
64
Two kinds of ions group together in an organized array called a _________ _________. Such a neutral unit is called a __________ _________.
Crystal lattice, formula unit
65
Ionic bonds form between atoms of _________ and ______-__________.
Metals, non-metals
66
Name the two steps to name ionic compounds.
1) name the cation first by using the element's name
2) name the anion second by using the first part of the element's name and changing the last part to "ide"
e.g. sodium chloride
67
What are multivalent elements? How are their formula names different?
Multivalent elements are elements with more than one stable ion. Ionic compounds containing multivalent elements must have Roman numerals in their names to indicate which ion is forming the compound.
68
What is a polyatomic ion? What are some suffixes for them?
They are made up of several non-metallic atoms joined together. The most common suffixes include "ate" and "ite" but "ide" can be found as well.
69
What is a molecule?
*review some common molecular compounds
It forms when two or more non-metallic atoms bond together.
70
What are covalent bonds?
They join the atoms in a molecule when atoms share electrons.
71
What is a molecular element?
It forms molecules made up of only one type of atom
72
What are diatomic molecules? Name them.
Each molecule is composed of two atoms. This differs from monatomic elements, whose atoms exist on their own.
Iodine
Bromine
Chlorine
Fluorine
Oxygen
Nitrogen
Hydrogen
73
What are polyatomic molecules? Name them.
Each molecule is composed of more than two atoms.
Sulfur
Phosphorus
Ozone
74
A _______ compound contains two elements.
binary
75
What are the three steps to naming molecular compounds without hydrogen?
1) name the first element
2) name the second elements with "ide" at the end
3) add prefixes indicating the number of atoms
**note that the prefix "mono" is not used for the first element
76
Name the characteristics of ionic compounds.
- solid at room temperature
- always conduct heat/electricity when dissolved in water
- high melting point
- crystalline formation/retention of crystal shape
- all dissolve in water to an extent
77
What is an electrolyte? How does it relate to ionic compounds?
An electrolyte is any solution that can conduct electricity. Solutions of ionic compounds are considered to be excellent electrolytes.
78
What is a solid precipitate?
It is a solid with low solubility that forms from a solution. Sometimes, when ionic solutions are mixed, a solid precipitate is the result.
79
Precipitation is the process of forming a ___________.
Precipitate.
80
What are some properties of molecular compounds?
- any state at room temperature
- low melting point
- form crumbly crystals
- do not conduct electricity
81
Explain the polarity of water.
Each water molecule has a slightly negative end (oxygen) and a slightly positive end (hydrogen). This makes water attracted to itself, making it easier for water to form a liquid.
82
In summer, oceans act as a heat ______, absorbing heat from the Sun and the air. In winter, they are a heat _______, radiating stored heat.
Sink, source
83
What is a reactant?
During a chemical change, reactants are the substances that reactant.
84
What is a product?
During a chemical change, the reactants produce a new substance(s) called the product(s).
85
What are some guidelines for the states of elements at room temp.?
- metals are all solid, except mercury, which is a liquid
- most diatomic elements are gases, except bromine and iodine
- bromine is a liquid
- iodine, sulfur, phosphorus, and carbon are solids
86
What are some guidelines for the states of compounds at room temp.?
- ionic compounds are solids
- an ionic compound that is very soluble is aqueous. One that is slightly soluble is shown as solid.
- molecular compounds are very difficult to protect
87
What is an exothermic reaction?
A reaction that releases energy, usually in the form of heat, light, or electricity.
88
What is combustion?
A chemical reaction that occurs when oxygen reacts rapidly with a substance to form a new substance and gives off energy. It's called burning. It is an exothermic reaction.
Oxygen reacts with a hydrocarbon
89
What is an endothermic reaction?
It is a reaction that absorbs energy.
90
Name two biochemical reactions. Determine whether they are endothermic or exothermic reactions.
- photosynthesis; endothermic
- cellular respiration; exothermic
91
What is a catalyst? What are enzymes?
A chemical that speeds up a reaction but is not used up by it. An enzyme is a biological catalyst.
92
What important conclusion did Antione Lavoisier come up with? Explain it.
The law of conservation of mass; it states that the total number of atoms present before a reaction is equal to the total number of atoms present after a reaction.
93
Describe a formation reaction.
element + element = compound
A + B = AB
94
Describe a decomposition reaction.
compound = element + element
AB= A + B
95
Describe a hydrocarbon reaction.
hydrocarbon + oxygen = carbon dioxide + water vapour
96
Describe a single replacement reaction.
A + BC = B + AC (metals switch)
D + BC = C + BD (non-metals switch)
97
Describe a double replacement reaction
AB + CD = AD + CB
98
What is a mole? What is 1mol equal to?
*mention Avogadro's number
A mole is the quantity that chemists use to measure elements and compounds. 1mol = Avogadro's number = 6.02 x 10^23
99
The mass of one mole of a substance is called...
molar mass
100
What is the factor-label method (formula)
m = n x M
m: quantity of matter (mass) in grams
n: number of moles
M: molar mass
101
What is an acid?
It's a compound that dissolves water to form solution with a pH lower than 7.
102
What is a base?
It's a compound that dissolves in water to form a solution a pH lower than 7.
103
What acid is found in our stomachs?
Hydrochloric acid
104
What does a pH measurement indicate?
How acidic or basic a substance is. It is a measure of the number of hydrogen ions in a solution.
105
What is a buffer?
It is a substance that can keep the pH of a solution nearly constant despite the addition of a small amount of acid/base.
106
Name the properties of an acid.
- sour
- does not feel slippery
- conductive
- corrodes metals
- <7 pH
- red litmus indicator
- hydrogen on the left side of formula
107
Name the properties of a base.
- bitter
- slippery
- no reaction with metals
- blue litmus indicator
- conductive
- >7 pH
- hydroxide often found reacting with a metal ion
108
What is an acid-base indicator? Mention litmus.
They are chemicals that are used to determine if a solution is an acid or base. They change colour pH depending on the pH of a solution.
Litmus is an indicator. In acid, blue litmus paper turns red, and in base, red litmus paper turns blue. In a neutral solution, litmus paper doesn't change colour.
109
What is an universal indicator?
It is a mixture of several indicators that change colour as the acidity changes.
110
What is a neutral substance?
It has a pH of 7 and is neither acidic nor basic.
111
What is process of neutralization?
The reaction between an acid and a base that produces water and a salt (saline solution).
112
Describe some issues related to chemicals. (3 points)
- workers can be exposed to toxic substances during manufacturing
- poisonous substances can escape into the environment during manufacturing
- some products are safe until they are thrown away (e.g. mercury)
113
What is physical dependence on a drug? What about psychological dependence?
Physical: occurs when the body becomes used to a drug and needs it to function
Psychological: the use of the drug is linked to certain moods or feelings. When the drug wears off, the feeling disappears
114
Describe alcoholism.
It's an addiction to alcohol. Alcohol is considered to be drug because of its effects on the body. The excessive use of alcohol can lead to destruction of the liver, kidneys, and brain cells. It can lead to physical/psychological dependence.
115
Name three high-risk behaviours that alcohol misuse can lead to.
- drunk driving
- binge drinking
- the use of alcohol in combination with some other drug
116
What is nicotine and where is it found?
It is a highly addictive drug, present in all tobacco products (cigarettes, cigars, chewing tobacco). It can cause physical/psychological dependence.
117
Cigarettes are the common source of nicotine, but there are more things that make them dangerous. Explain.
Cigarette smoke is many times more harmful than the most polluted air. it contains large amounts carbon monoxide, a poisonous gas. 30% of percent of the smoke is composed of tar.
Smoking cigarettes damages the respiratory and circulatory systems. Smokers have a much higher chance at developing lung cancer than non-smokers.
The smoke is also dangerous to non-smokers. Passive smokers are those who are exposed to smoke.
118
What is benzene? What is it used for?
A hazardous chemical that is both toxic and flammable. It is used to make dyes and medicines. It is a regulated substance, meaning it must be used according to strict guidelines.
119
Name two chemistry related careers.
- food technologist
- cosmetics formulator
120
We can manage hazardous substances through a combination of:
(4 points)
- understanding the properties of materials
- using careful and clever design and process engineering
-placing personal safety and environmental protection as the top priority
- enforcing effective regulations
