Mid Term Exam: ST Flashcards
1
Q
What are the sub atomic particles?
A
- Protons
- Neutrons
- Electrons
2
Q
What does the atomic number represent?
A
The number of protons.
3
Q
What makes an atom of neutral charge?
A
Same number of protons and electrons.
4
Q
What makes a positive ion?
A
More protons than electrons.
5
Q
What makes a negative ion?
A
More electrons than protons.
6
Q
What makes an atom chemically stable?
A
When the element has a full outer shell.
7
Q
How do you make a chemically unstable element stable?
A
By giving, taking or sharing electrons.
8
Q
What are trends in the periods of the periodic table?
A
- The number of valence electrons goes up one from left to right.
- Each period has the same number of shells.
9
Q
What are trends in the groups of the periodic table?
A
- The number of shells goes up one from top to bottom.
- Each group has the same number of valence electrons.
10
Q
What are valence electrons?
A
The number of electrons on the outer most shell.
11
Q
Which group is unreactive?
A
Noble gases because they have full shells, they are complete.
12
Q
Which groups are highly reactive?
A
Alkali metals and Halogens because they only need to gain or lose one electron to be complete.
13
Q
What are characteristics of metals?
A
- Malleable
- Ductile
- Shiny (has lustre)
- Conducts electricity and heat
- Reacts with acid
- Melt at high temperatures
14
Q
What are the characteristics of non-metals?
A
- Brittle
- Non-malleable
- Non-ductile
- Dull
- Non-conductive
- Non-reactive
- Melt at low temperatures
15
Q
What are characteristics of metalloids?
A
Has characteristics of both metals and non-metals.
16
Q
What makes a positively charged ion?
A
When an element loses electrons.
17
Q
What makes a negatively charged ion?
A
When an element gains electrons.
18
Q
What’s a cation?
A
Positively charged ion.
19
Q
What’s an anion?
A
Negatively charged ion.
20
Q
What do electrolytes do?
A
Conducts electricity in water.
21
Q
What’s a physical change?
A
A change in state.
22
Q
What’s a chemical change?
A
Forms a new substance.
23
Q
What is oxidation?
A
A reaction with oxygen.
24
Q
What is decomposition?
A
Bigger molecules break into smaller molecules.
25
What is the conservation of matter?
Same amount of atoms at start and end.
26
What is an aqueous solution?
When the solvent is water.
| 1 mL of water = 1g
27
What's parts per million?
It is used for really teeny tiny amounts of stuff, for weak concentrations. It is the number of parts of solute in a 1 000 000 parts of solutions.
28
What is one ppm equaled to?
1g/1 000 000g
1g/1 000 000mL
1mg/1L *aqueous
29
What is the concentration of 15g NaCl in 250 mL, in g/L?
60g NaCl/L
30
What is 500mg/L in g/100mL?
0. 05g/100mL
| 0. 05%
31
What is 0.14mg/200mL in ppm?
0.7 ppm
32
How many grams/125mL when 5000 ppm?
0.625g
33
0.002% of Ca in ppm and g/L?
20 ppm
| 0.02g/L
34
0.025g/mL, how many grams in 100mL, 250mL and ppm?
25 000 ppm
2. 5g/100mL
6. 25g/250mL
35
What is electrolytic dissociation?
Compounds will separate into 2 ions when dissolved in water.
36
What are electrolytes?
Substances that conduct electricity when dissolved in water.
37
What are the three types of electrolytes?
Acids, bases and salts (all salts are neutral).
38
What is the formula for electrolytic dissociation?
Compound ----- (H2O) -----> charged element(s) + charged element(s)
39
What does more dissociation mean?
More dissociation = more charges, so stronger electrolytes.
40
What is the formula for acids?
Begins with H, ends with non-metal or anion. H+ dissociation from the anion.
41
What is the formula for bases?
Begins with metal or cation, ends with OH. OH- dissociation from the cation.
42
What is the formula for salts?
Cation dissociation from the anion.
43
How do pH amounts vary?
pH amounts vary by a factor of 10.
44
When do we consider the substance a strong acid?
When all or most of the H+ dissociates from the anion.
45
When do we consider the substance a strong base?
When all or most of the OH- dissociates from the cation.
46
What is a community?
It is a "group" formed when all the different populations of species share the same habitat.
47
How do your measure biodiversity?
- Species richness
| - Relative abundance
48
What is species richness?
It is the total number of species in a community.
49
What is relative abundance?
It is the number of species in relation to the total organisms in the community.
50
When is there a high biodiversity?
When the species richness is high and the relative abundance in similar (relatively equal).
51
What are interspecific interactions?
They are relationships between individuals of different species.
52
What are infraspecific interactions?
They are relationships between individuals of the same species.
53
What are the types of interspecific interactions?
- Competition
- Predation
- Parasitism
- Mutualism
- Commensalism
54
What is competition?
- It is a relationship where different species compete for the same limited food resources.
- Species that can adapt will profit best from available resources.
- Strong competition can limit the presence of a species.
55
What is predation?
- When one species kills another for food.
- Can include herbivores and carnivores.
- Populations of predators influence population of prey.
- Prey must be adaptable to protect or defend themselves from predators.
56
What is parasitism?
- Relationship in which one species profits from another species, which is injured by the interaction.
- Usually a parasite does not kill its host because it needs the host to survive (host can become sick from the parasite or die).
57
What is commensalism?
- One species profits from another without harming or helping it (its unaffected).
58
What is mutualism?
- Relationship in which 2 different species benefit and the relationship is mutually beneficial.
59
What is a population?
It is a group of organisms of the same species that live in a shared habitat at a give point in time.
60
What is the population characterized by?
- Size
- Growth
- Density
- Distribution
61
What is population size?
It is the number of individuals in a population. It can increase, decrease or stay constant over time.
62
What are factors that affect population size?
- Natality
- Mortality
- Immigration
- Emigration
63
How do we estimate the size of a population?
- Counting
- Sample area
- Mark and recapture
64
How to do sample area?
Divide areas of land into equal plots, count the number of individuals in each plot, calculate average, multiply by total area then divide by area per plot.
Average # of individuals / Area per plot = Total population / Total area
65
How to do mark and recapture?
```
Capture and mark, release, recapture.
# marked in sample 1 (M) / Size of whole population (N) = # marled in sample 2 (r) / Total caught in sample 2 (n)
```
66
What is population growth?
It is the increase, decrease or consistency in the growth of a population.
67
When does the population increase?
When natality + immigration > mortality + emigration
68
When does the population decline?
When natality + immigration < mortality + emigration
69
When does the population stay constant?
When natality + immigration = mortality + emigration
70
What affects population?
Time affects population.
71
What is carrying capacity?
It is the maximum number of individuals that can be supported in a given area. It is when the resources in an area are limited there is a limited population that can be supported.
72
When does population decline?
When carrying capacity is reached and exceeded.
73
What are limiting factors? Give examples.
Factors that limit the growth and survival of a population.
| Ex: Biotic and abiotic factors
74
What are biotic factors? Give examples.
```
They are living factors that can have an impact on a population.
Ex:
- Food
- Bacteria
- Predation
- Humans
- Parasites
- Limited plants
```
75
What are abiotic factors? Give examples.
```
They are non-living ecological factors of physical or chemical nature that can affect a population.
Ex:
- Sunlight
- Atmospheric composition
- pH
- Temperature
- Pheremones
- Water
- Storms, droughts, floods, volcanic activity, deforetation, pollution
```
76
How to calculate population density?
D = number of individuals of a species (n) / surface area or volume occupied (a or v)
77
What is population distribution?
It is the way in which individuals are spread out over a territory.
78
What are the 3 ways in which individuals are spread out in a territory?
- Clumped
- Uniform
- Random
79
What is clumped distribution?
It is when individuals form clumps that improve chance of survival. The most common.
80
What is uniform distribution?
It is when individuals maintain an equal distance between each other, this indicates a strong competition for space and resources.
81
What is random distribution?
This occurs when there are the same conditions over a territory and a little competition between individuals, or when the conditions are just random. Spread out randomly. The least common.
82
What are important characteristics in the biological cycle and how do they vary?
- Frequency of reproduction
- Age of maturity
- Reproductive maturity
- Number of offspring
These characteristics vary by species.
83
How do the size of an organism relate to the number of offspring it produces?
Usually the larger the organism, the lower the number of offspring and the smaller the organism, the larger the number of offspring.
84
What is an ecosystem?
It's a community of species interacting in a given area (habitat).
85
What are the characteristics of living things?
- Made out of cells
- Acquire and use energy
- Grow and develop
- Reproduce
- Respond and adapt to their environment (within reason)
86
What are trophic relationships?
The feeding relationships between organisms that eat and organisms that are eaten, represented by a food chain.
87
What are the 3 trophic levels?
- Producer
- Consumer
- Decomposer
88
What are food chains?
They are representations of the trophic relationships between different living things.
89
What are food webs?
They are a group of interrelated food chains.
90
Where do the arrows point in food chains and webs?
In the direction of the energy flow.
91
What are ecological pyramids?
A representation of the flow of energy and matter in the form of a pyramid, in which each trophic level is represented by a rectangle whose size is proportional to the amount of biomass it has.
92
What is energy flow?
It is the flow of matter and energy that are transferred/transformed in a food chain.
93
What is biomass?
It is the mass of all the organic matter in an ecosystem. It represents the total mass of living matter in an area at any given time.
94
Why do both energy and biomass usually decrease with each trophic level?
Both energy and biomass usually decrease with each trophic level since organisms give off more energy to breathe, eat, reproduce, move, etc. while moving up. And going up the organisms get lighter because there are less of them, so lower biomass.
95
What do trophic levels affect?
Trophic levels affect relative abundance and population size for the whole ecosystem to remain in balance.
96
How much energy is transferred from one trophic level to the next?
10% of the energy is transferred.
97
Is the rainforest or the tundra more productive?
The rainforest because there's more rain (more water to make things grow) and it's hotter (so more active, more things being produced).
98
Who are producers?
- They are autotrophs (produce their own food)
- They convert inorganic material into organic material into organic material using light (photosynthesis (producing sugar)).
99
What is primary productivity?
It's the total quantity of new organic material made by the producers in an ecosystem over a certain period.
100
What does primary productivity depend on?
It depends on factors such as sunlight, carbon dioxide concentration, availability of nutrients, water and temperature.
101
What are consumers?
They are heterotrophs (they get their food from a variety of other living things).
102
What are the 3 levels of consumers?
- Primary consumers (herbivores): eat plants
- Secondary consumers (carnivores): eat other consumers
- Omnivores: eat from many levels, autotrophs, other consumers.
103
What are decomposers?
They eat dead organisms and waste, breaking it down into inorganic matter (respiration). They are connected to all the trophic levels.
104
What is chemical recycling?
It occurs when decomposers make inorganic matter available in an ecosystem by breaking down organic matter.
105
Where does chemical recycling occur?
At each trophic level in a food chain a certain amount of material is recycled by decomposers back into nutrients that producers can use.
106
What is an ecological disturbance?
It is an event that disrupts an ecosystem, that can lead to the reduction or elimination of organisms (or species) and change in the availability resources.
107
What are the types of disturbances?
- Natural disturbances
| - Human disturbances
108
What are natural disturbances? Give examples.
```
They are disturbances that occur due to environmental phenomena.
Ex:
- Storms
- Fires
- Floods
```
109
What are human disturbances? Give examples.
```
They are disturbances that are man made, the main form of ecological disturbances on Earth.
Ex:
- Oil spills
- Deforestation
- Nuclear meltdown
```
110
What is ecological succession?
The series of changes that occur over time in an ecosystem after a disturbance and that continue until the balance of the ecosystem is restored.
111
What are the reactions of the carbon cycle?
- Photosynthesis
- Respiration
- Combustion
112
What reduces the amount of carbon in the atmosphere?
- Dissolution of carbon in water
| - Photosynthesis
113
What adds to the amount of carbon in the atmosphere?
- Combustion
- Respiration
- Volcanic eruption
- Forest fires
- Decomposition
114
What is the greenhouse effect?
1) Heat from sun warms the Earth
2) Earth radiates heat
3) Greenhouse gases reflect heat back (keep Earth warm)
115
What's the positive to the greenhouse effect?
The temperature would be -28*C without it (it keeps the Earth warm).
116
What's the negative to the greenhouse effect?
If there's too much it will contribute to climate change/global warming.
117
What's nitrogen fixation?
When bacteria convert N2 to NO2 or NO3.
118
What's ammonification?
When bacteria concert NO2 or NO3 to NH3 or NH4.
119
What is nitrification?
When bacteria convert NH3 or NH4 to NO2 or NO3.
120
What's denitrification?
When bacteria convert NO2 or NO3 to N2.
121
What is the order of the steps in the nitrogen cycle?
1) Nitrogen fixation
2) Ammonification
3) Nitrification
4) Denitrification
122
What is a better alternative to fertilizer used to replace nutrients in agriculture?
Compost - no excess nutrients.
123
What are the 5 chemical reactions?
- Photosynthesis
- Respiration
- Combustion
- Oxidation
- Neutralization
124
What's photosynthesis?
6 CO2 + 6 H2O + Energy -----> C6H12O6 + 6 O2
125
What's respiration?
C6H12O6 + 6 O2 ------> 6 CO2 + 6 H2O + Energy
126
What's combustion?
Element + Oxygen ------> Carbon dioxide + Water
127
What are the sources of combustion?
- Volcanic eruptions
- Forest fires
- Fossil fuels
128
What's oxidation?
Oxygen is a reactant.
129
What's neutralization?
Acid + Base -------> Salt + Water
130
What is the law of conservation of mass?
What goes in, must come out.
131
What is the lithosphere?
It is the hard shell of the Earth, consisting of the crust and the top most part of the upper mantle (magma).
132
What are minerals?
They are inorganic substances, that come from the Earth and not from living things.
133
What are minerals made up of?
Some are made up of one type of atom.
| Some are made up of several.
134
How do we extract minerals?
We use mining to locate and extract them.
135
What are mineral deposits?
If the mineral is found at the surface of the lithosphere, ore can be collected and then separated.
136
What is ore?
- Rock and the mineral
| - Heterogeneous
137
What are the impacts of mining?
- CO2 emissions mess with the surface, it disturbs the ecosystem.
- Changes water flow
- Produces heat
- Uses lots of water (for a cooling system)
- Scars the Earth (seen from space)
138
How is soil created?
Through the process of erosion of the parent rock (solid part of Earth's crust.
139
What are the soil horizons?
Layers of soil.
- Organic matter
- Topsoil
- Subsoil
- Fragmented parent rock
- Unaltered parent rock
140
What does the organic matter layer of soil contain?
Humus.
141
What does the topsoil layer of soil contain?
A mix of humus and minerals.
142
What does the subsoil layer of soil contain?
Nutrients for small minerals and trees.
143
What is the fragmented parent rock layer of soil made of?
Disintegration of parent rock.
144
What is the unaltered parent rock?
The starting point of soil.
145
What alters the soil and how?
- Oxidation (mineral + O2 ---> mineral oxide)
- Neutralization (alters pH of soil)
- Decomposition (organic ----> inorganic + CO2)
- Contaminants
146
What is permafrost?
A layer of permanently frozen soil, that's been at 0*C or lower for over 2 years.
147
What are consequences of permafrost thawing?
- Loss of infrastructure
- Landslides
- Release of stored carbon as CH4 (powerful greenhouse gas) contributing to global warming acceleration
- Increase of vegetation
148
What is the hydrosphere?
The Earth's outer layer of water, uniting water in solid, liquid, gas states.
149
What is a catchment area?
An area of land where lakes and rivers all empty into the same larger body of water. It catches rain, surface water and ground water over that region.
Watersheds/drainage basins
150
What is the catchment area determined by?
Natural lines that are formed by the land (ridges). Water flows down slopes towards the basin.
151
What causes human disturbances on watersheds?
- Creation of a reservoir upstream from a hydroelectric power plant can disturb the ecosystem
- Contaminants that are upstream of the basin can be spread anywhere downstream (red town, blue town experiment)
152
What plays an essential role in regulating climate? How?
The oceans by absorbing heat and standardizing the temperature of the Earth.
153
What are factors that influence water temperature? How?
- The season (angle of sunlight to Earth as we rotate)
- The latitude (closer to equator = hotter)
- The depth (deeper = colder, less sunlight)
154
What is salinity?
The concentration of salt.
155
Where does salt in the hydrosphere come from?
The weathering of the lithosphere (dissolved minerals).
156
How will hot and cold water react when mixed?
Cold water will sink due to high density and warm water will float due to being less dense.
157
How will salt and pure water react when mixed?
Salt water sinks because it is more dense than pure water (more dense = sinking).
158
What is an ocean current?
The movement of seawater in a certain direction.
159
What are the 2 types of marine currents?
- Surface currents
| - Deep currents
160
What are surface currents?
They are (horizontal) currents that are mostly generated by wind.
161
What are deep currents?
They are (vertical) currents caused by differences in temperatures, salinity and densities. They are controlled by thermohaline circulation.
162
What is the cryosphere?
The layer made up of frozen water on Earth.
163
What are ice floes?
They are ice packs, slightly salty ice floating on the ocean. They form when the surface of water freezes due to cold temperatures and break into sheets.
164
What are glaciers?
When snow is compressed on land.
165
What are ice bergs?
Broken pieces of glaciers that fall into the water.
166
What are impacts of melting ice?
- Thermohaline currents are disturbed
- Reduction of reflectivity, land and oceans absorb more heat
- Increase in sea level due to accelerated thawing of glaciers and ice bergs.
- Losing Earth's cryosphere
- Loss of habitat when pack ice melts
167
What is thermohaline?
A combination of surface and deep currents, create ocean circulation of temperature and salinity distribution. Mixes water around the world (warm water near equator to poles, vise-versa), regulates Earth's climate and overall temperature.
168
What affects density in oceans?
Temperature and salinity of water.
169
What are the effects of less ice on the climate?
No ice means the land and water will absorb more heat because the ice isn't reflecting sunlight.
170
What is the albedo?
Measure of how much light that hits a surface is reflected without being absorbed.
171
What are the effects melting pack ice on climate?
- Melted ice pack water is less salty than ocean water, so less dense, doesn't sink as much, so affects thermohaline circulation, which worsens climate change.
- Less surface area to reflect sunlight, more heat absorbed by ocean water
- Loss of habitat
172
What are consequences of melting glaciers?
- Reduction of reflectivity
| - Rise in sea levels
173
How is thermohaline altered by global warming?
Change in densities.
- Glaciers are melting, diluting salt concentration and making water colder.
- Evaporation of ocean at equator - increasing concentration of salt.
- Albedo effect
174
How does altered thermohaline generate climate change?
- Melting of pack ice.
175
What causes tides?
The gravitational pull of the moon.
176
How many tides in one day?
2 high tides, 2 low tides
177
What is the atmosphere?
The layer of air surrounding the Earth.
178
What is the atmosphere composed of? What are these gases necessary for?
O2 + CO2: cellular respiration + photosynthesis
Water vapour: cloud formulation + precipitation
- Acting as a shield and blocking out the UV rays
- Ensuring a stable climate on Earth by retaining heat
179
What are the layers of the atmosphere?
- Exosphere
- Thermosphere
- Mesosphere
- Stratosphere
- Troposphere
180
What determines atmospheric pressure?
Collisions between particles, the more there are, the higher the pressure.
181
What is the affect altitude has on atmospheric pressure?
High altitude - density + temperature decrease - low pressure.
182
What is the affect temperature has on atmospheric pressure?
Temperature rises - density decreases - warm air rises.
183
What is convection?
Cycling/movement of the air: rises above humid regions at the equator and head toward the poles, then sink over cold regions. At the same time, Earth rotates, cold polar air makes its way to the equator.
184
What is the Coriolis effect?
Rotation of the Earth causes the wind to bend.
185
What are air masses?
Large regions of the atmosphere with uniform temperature, density, pressure and humidity that can change the weather due to winds.
186
What happens when two air masses meet?
- They form a front (hot or cold).
- Warm air rises (on top), cold air sinks (under)
- We get clouds and rain
187
What's a warm front?
- Mass of warm air moves toward mass of cold air
| - Warm air rises over cold and creates cloudy weather and showers
188
What is a cold front?
- Mass of cold air meets mass of warm air
- Warm air rises quickly and in a steep slope over the cold air, then cools
- Heavy rain and wind. Storms, blizzards
189
What is a cyclone?
- Air gets hot, air mass less dense
- Air mass lighter and rises, leaving an empty space under it, a depression. Space becomes low pressure
- Rising air encourages cloud formation and often results in precipitation (cyclone)
190
What is an anticyclone?
- Air sinks, pressure increases
- Air density increases and mass of air becomes heavier and falls toward the ground creating area of high pressure (creating anticyclone)
- Cold air, no clouds or rain, clear skies and stable weather
191
What is the greenhouse effect?
- Natural process that retains heat by trapping greenhouse gases (CO2, H2O, CH4) in the atmosphere
- Without it, average temperature of Earth would be -18 (very cold)
192
What are human disturbances on greenhouse effect?
- Combustion of fossil fuels, deforestation, a lot of cows, palm oil
- Humans use/emit too many greenhouse gases, that causes the atmosphere to trap too much heat (before humans disturbed it, more greenhouse gases were escaping than staying in)
193
What are the different energy resources?
- Fossil fuels
- Nuclear energy
- Geothermal energy
- Hydraulic energy
- Wind energy
- Solar power
194
How are oil, natural gas, coal formed? What are the advantages and disadvantages of fossil fuels?
- Oil and natural gas formed by dead small marine animals and algae, sink to bottom of the sea, covered with silt, sand, minerals
- Coal formed from terrestrial swamps being buried and compressed by silt and sand
Advantages: Less expensive, easy to burn, a lot of immediate energy, transportable, easily accessible
Disadvantage: Non- renewable, releases CO2 (not green)
195
What is nuclear energy? What are the advantages and disadvantages?
- Energy is produced by atomic fission, mainly uranium (which is split)
Advantages: Green, little amounts of stuff produce a lot of energy
Disadvantages: renewable, radioactive waste
196
How is geothermal energy formed? What are the advantages and disadvantages?
- From the internal heat of the Earth's molten rock. Water deep underground - heated by lava - rise to surface - transformed into electrical energy
Advantages: Green, renewable, can be used remotely
Disadvantages: Not good everywhere, expensive to set up
197
What is hydraulic energy? + marine currents and tides? What are the advantages and disadvantages?
Energy from moving water (mechanical energy --> electrical energy)
Marine currents and tides create large quantities of energy. Tidal power plants use tides to produce electrical energy.
Advantages: Green, renewable
Disadvantages: Disrupts ecosystem, may kill fish, expensive to set up
198
What is wind energy? What are the advantages and disadvantages
- Energy that can be drawn from the wind
Advantages: Renewable, green
Disadvantages: Noisy, unpredictable, can't be stored
199
What is solar power? What are the technologies that change solar to electrical energy? What are the advantages and disadvantages?
- Nuclear reactions that transform H --> He. Produces energy which is dispersed as radiation through the atmosphere.
Advantages: Renewable, green
Disadvantages: No sun = no energy, expensive to set up, energy not easily stored
1) Passive heating systems: positioning a house to maximize the heat and light from the sun, naturally heats air. A: Once done, always heating. D: Summer, too hot.
2) Photovoltaic cells (solar panels): Sunlight hits the material, which allow the electrons to move = electric current. A: Portable. D: Expensive, position of panels.
3) Solar collectors: glass panels that capture heat to warm up the air, home or pools. A: Easily used. D: Could get too hot.
200
What are the parts of the fire triangle?
Heat (temp.), fuel and oxidizing agent.
