Science Flashcards
Atomic number
number of protons in the nucleus of an atom. The atomic number determines which element an atom is
Mass number
The number of protons and neutrons in the nucleus of an atom
Alkaline metals
Highly reactive metals in group 1
Alkaline earth metals
Reactive metals in group 2
Halogens
Non metals in group 17
Noble gases
Inert gasses (non reactive) in group 18
Transition metals
Metallic Elements group 3-12
Metals
Elements that have high shine/lustre, are good conductors of heat and electricity, are ductile and malleable, have high melting points, except mercury and are metal at room temperature except for mercury
Non - metals
elements that are dull or glassy, brittle, not malleable, poor conductors of heat and electricity and have low melting points. Most non metals are gases at room temperature
Metalloid
Elements that that have the appearance of metals but not all the other properties
Molecules
Particles with two or more atoms joined together
Electron shell diagram
Diagram showing electrons in their shells around the nucleus of an atom
Shell
Energy levels around the nucleus of an atom into which electrons are arranged
Electron configuration
An ordered list of the number of electrons in each shell, from inner (low energy) to outer (higher energy) shells.
-2,8,8,2-
Neutral
Having equal amounts of negative and positive charge and therefore no overall electric charge.
Ions
Atoms or groups of atoms that have lost or gained electrons
Cations
Atoms or groups of atoms that have lost electrons and are positively charged
Anions
atoms or groups of atoms that have e gained electrons and are negatively charged
ionic compounds
Compounded containing positive and negative ions held together by the electrostatic force
Properties of ionic compounds
Made up of positive and negative ions, usually solids at room temperature, high melting points due to strong electrostatic force, dissolvable in water, aqueous solutions normally conduct electricity
Ionic bond
Attractive force/attraction between ions with opposite electrical charge
Molecular formula
Statement of the elements in a molecule showing the relative number of atoms of each kind of element
Valency
Is equal to the number of electrons that each atom needs to gain, lose, or share to feel it’s outer shell
Displacement reactions
chemical reactions involving the transfer of electrons from the atoms of a more reactive metal to the ions of a less reactive metal
Alloy
mixture of several metals or sometimes a metal and a non-metal, such as carbon
Rate
How fast an event occurs eg the speed of a reaction
What can speed up a chemical reaction?
Increase in temperature, surface area increase,
concentration of the reactants, exposure to light
Catalyst
Chemical that speeds up the reaction but is not consumed in the reaction
examples of Industry catalysts
iron + iron oxide is used to produce ammonia gas which is used for fertiliser and explosives, vanadium oxide used to produce sulfuric acid.
Everyday catalysts
cars fitted with catalytic converters used to reduce the pollution of CO and N20, contact lenses using hydrogen peroxide
Enzymes
Biological catalyst, helps you digest food, break down toxic waste and other chemical processes
Amylase
Enzyme in saliva that breaks down starch into sugar
Catalase
Enzyme in the liver involved in the break down of hydrogen peroxide a toxic waste product from the cells In the body
Three electron configuration rules
2n (squared) max electrons per shell, Valence shell holds had 8 electrons, all elements prefer 8 valence electrons expect shell 1 which likes 2)
How to work out the 2n squared rule?
Substitute in the shell number eg. 2(3)^2 for shell three
Period
Number of shells
Groups
Number of electrons in valiant shell
Neutralization
Reaction between an acid and a base. Salt and water are the products of this type of reaction. Eg. Antacid (base) neutralizes the hydrochloric acid (acid) in the stomach
What are the 5 different types of reactions
Metal hydroxide + acids —> Salt + Water
Metal Oxide + Acids —> Salt + Water
Metal Carbonate + Acids —> Salt + Water + CO2
Metal Hydrogen Carbonate + Acids —> Salt + water + CO2
Metal + Acid —> Hydrogen Gas + Salt
Monoatomic
Compounds that only have 1 of each atom (NaCl)
Diatomic
Compounds that have 2 of an atom (MgCl2)
What is the biosphere
The life support system of the earth
Atmosphere
Layer of gasses around the earth.
Lithosphere
The outermost layer of the earth. Includes the crust and the upper most part of the mantle
Hydrosphere
The water on the earths surface
Ozone layer
a layer in the stratosphere, about 25 km above Earth, that has high concentrations of ozone gas. The ozone layer absorbs over 90 per cent of the sun’s ultraviolet light
Chlorofluorocarbons
organic compounds used as coolant agents, propellants in aerosols, and solvents. Their manufacture is being phased out as they also cause damage to the ozone layer.
What is the carbon cycle
The carbon cycle models how carbon moves through the biosphere. Carbon travels from the non-living atmosphere to living things when carbon dioxide is absorbed by photosynthetic organisms (such as plants).
What is radiant heat
Heat transferred by radiation, eg from the sun
What is the greenhouse effect
a natural effect of the Earth’s atmosphere trapping heat, which keeps the Earth’s temperature stable. The sun’s energy passes through the atmosphere and warms the Earth. Heat energy radiated from the Earth cannot pass through the atmosphere and is trapped.
What are greenhouse gasses
gases found in the atmosphere that contribute to the greenhouse effect, trapping the sun’s heat (for example, carbon dioxide)
Define enhanced greenhouse effect
an intensification of the greenhouse effect caused by pollution adding more carbon dioxide and other greenhouse gases to the atmosphere; associated with global warming
What is global warming
the observed rise in the average near-surface temperature of the Earth
Cellular respiration
the chemical reaction involving oxygen that moves the energy in glucose into the compound ATP. The body is able to use the energy contained in ATP.
Ice cores
samples of ice extracted from ice sheets containing a build-up of dust, gases and other substances trapped over time
Permafrost
soil on or below the surface of very high mountains in the polar regions that is permanently frozen
Geosequestration
the process that involves separating carbon dioxide from other flue gases, compressing it and piping it to a suitable site
Speed
Thee rate of change of distance with respect to time
Velocity
Rate of change of displacement with respect to time
Displacement
Distance between origin and destination
Four main layers of the atmosphere
troposphere, stratosphere, mesosphere and thermosphere
what are 4 characteristics of the Troposphere
- Where weather occurs (water cycle)
- 90% of atmospheres mass
- Temp decreases with altitude, 6 degrees C, averages -50 at top
- 16km at equator, 8km at poles
what are 3 characteristics of the stratosphere
- extends from 10km to 50km above ground
- Contains high levels of ozone
- Less dense and temp increases with altitude
what are 3 characteristics of the Mesosphere
- Extends 80 km high
- Gases absorb very little UV radiation
- Gases are less dense, temp decreases with altitude
what are 3 characteristics of the Thermosphere
- Extends to almost 600km high
- Temp increases with altitude
- Reflects radio waves and temps get as hot as 1,500 degrees
what are all the layers of the atmosphere
Troposphere > Tropopause > Stratosphere > Stratopause > Mesosphere > Mesopause > Thermosphere > Exosphere
what does the pause mean in tropopause, stratopause etc
A pause in temperature change
What is the atmosphere made up of?
- 1% nitrogen
- 9% Oxygen
- 9% Argon
- 035% CO2 and rising
why is there so much nitrogen in the atmosphere
Most stable gas, reacts with nothing and stays in the atmosphere forever
Study carbon cycle
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Would ad pic but idk how
Ur bad whoever wrote this you have to use the website -_-
You need the pro version lmao
What gasses are involved in global warming
Carbon Dioxide, Nitrous Oxide, Methane, CFCs, HFCs and ozone(O3)
what is the major cause of global warming
The burning of fossil fuels such as coal and oil has resulted in increased levels of greenhouse gasses (such as nitrous oxide and co2) in our atmosphere that are trapping heat, causing the atmosphere to heat
what are two other causes of global warming
Grazing animals like cattle and sheep produce large amounts of methane as a waste product. most of the nitrous oxide is produced by the action of bacteria on fertilized soil and urine of grazing animals
What are the 5 effects of global warming
Melting ice caps, rising sea levels, more extreme weather events, ocean acidification and increased coastal flooding
what are 3 solutions to global warming
Use renewable energy (wind or solar), stop using fossil fuels and invest in energy efficient appliances
How do you calculate average speed
Distance over time (d/t)
How to you calculate average Velocity
displacement over time (s/t)
what does V and U stand for when calculating acceleration
V - Final Velocity
U - initial velocity
How do you convert hours to seconds, seconds to hours
hours to minutes (x60) minutes to seconds (x60)
seconds to minutes (÷60) minutes to hours (÷60))
how to you convert cm to km, km to cm
cm to m (÷100) m to km (÷1000)
km to m (x1000) m to cm (x100)
how do you convert ms-1 to kmh -1 (per second)
ms-1 to kmh-1 (x3.6)
kmh-1 to ms-1 (÷3.6)
how do you calculate average acceleration
acceleration = V - U over T
Define acceleration
The change in speed in metres per second per second
?What does the biosphere contain?
Consists of he atmosphere, lithosphere, hydrosphere and biota (Living things)
