science assessment term 2 Flashcards
what is froth flotation?
A method using special chemicals to separate copper minerals from waste rock
1. ores are dug out of the ground
2. these are crushed into fine powder
3. powder is then mixed in with water and chemicals that are similar to detergent
4.then air is blown into the bottom of the container,
5.the malachite (mineral ore) is then carried to the surface by the air bubbles as malachite sticks to the chemicals
6. the waste rock then sinks to the bottom of the tank, unable to stick to the chemicals
7. the malachite then gets collected as they skim the surface to collect the copper it’s then further treated to extract pure copper
how do we use magnets to separate iron?
A method using iron’s magnetic property to separate iron and waste rock
1. rock containing iron minerals are crushed into fine powder.
2. then dropped onto a conveyer belt where a magnetic roller appears
3. the roller attracts the pieces that contain iron as it is magnetic
4. the waste rock are not magnetic and therefore do not attach and drop down
5. iron containing pieces are further collected for proccessing
fraction distillation
a method used to separate the different components of crude oil using boiling point
1.the crude oil is placed on a equipment called a fractioning column.
2. this is then heated
3. then each liquid evaporates at different times rising up
4. then it cools below boiling point and turns into liquid
5. it exists the column through a tube
Explain why filtration is used to separate various mixtures based on the properties of the
mixtures
Filtration separates solids from a liquid based on their solubility and particle size
Explain why sieving is used to separate various mixtures based on the properties of the
mixtures
sieving is used to separate small solids from larger solids or liquids which is based on the particle size
Explain why chromatograph is used to separate various mixtures based on the properties of the
mixtures
Chromatography separates different chemicals of a solution based on their solubility
Explain why decanting is used to separate various mixtures based on the properties of the
mixtures
decanting is used separate soluble and insoluble solids or liquids which is based on their density and solubility
Explain why evaporation is used to separate various mixtures based on the properties of the
mixtures
evaporation is used to regain the solute from the solvent based on their boiling points
Explain why crystallisation is used to separate various mixtures based on the properties of the
mixtures
Crystallisation removes a solute from the solvent based on their solubility
pure substance
a substance made up of one material or particle
examples of pure substance
compounds and elements
mixtures
a substance made of two or more substances
examples of mixtures
salad
solutions
is a type of mixture when one substance separates and spreads out evenly into another substance
solute
is the component of a solution that is spreading out or dissolving evenly into the solvent
solvent
is the component in a solution that is capable of dissolving another substance
Aqueous solution
is a type of solution where the solvent is water
observation
is something that you have witnessed or experienced
inference
is a possible explanation for an observation based on reasoning
what’s the difference between an observation and a inference?
an observation is generally a statement of fact but inferences show a relationship between two things
biology
biology is a large field of studying living organisms
chemistry
chemistry is the exploration of matter and their properties and reactions
physics
physics is the study of the universe and the nature and properties of matter and energy
earth science
earth science is the study of physical rules of the earth and it’s atmosphere
space science
space science is the exploration of space
Gravitational force
the force of gravity is the force with which the earth, moon or other massively large objects attract another object towards itself
electrostatic
the attractive or repulsive interaction between any 2 charge objects
Magnetic force
a magnetic force is an attractive or repulsive interaction between the ends of 2 magnets
mechanical force
a mechanical force is a force applied to an object by a person or another object.
normal force
the normal force is a support force exerted upon an object that is in contact with another stable object.
friction force
the friction force is the force exerted by a surface as an object moves across something or makes an effort to move across
air resistance force
the air resistance is a special type of frictional force that acts upon objects as they travel through the air. (opposes the motion of the object)
Tension
the tension force is the force transmitted through a string, rope, cable or wire when it is pulled by forces acting from the opposite
forces scientific definition
is any action that causes something to be pushed, pulled or twisted.
everyday examples of mixtures
saltwater, salad, cake, tea, coffee
examples of solvents
water, vegetable oil, white vinegar, lemon juice
examples of water as the solvent in daily life
cooking - Water is used as a solvent to dissolve salts, sugars, and flavors in cooking.
hydration - the water we drink is not pure and is often mixed with chemicals and essential minerals
examples of water as the solvent in industries
cleaning - for cleaning equipment, surfaces, and facilities, water is mixed with chemicals that kill bacteria
examples of water as the solvent in manufacturing
aquatic life - water is often mixed with oxygen, nutrients for creatures
contact force
contact force is any force that occurs as a result of two things making contact with each other
non contact force
non contact force acts on an object without physically in contact with it.
spring force
the spring force is the force exerted by a compressed or stretched spring upon any object that is attached to it.
define and describe constant speed as stationary
an object is stationary when it is not moving and remaining the same, meaning the forces are balanced
stationary examples
- book lying on the table, shows as that the gravitational force pulling down the book is balanced by the normal force pushing up
define and describe moving constant speed
an object moving at constant speed means the velocity is steady as both the magnitude and direction remains the same. here the forces are still balanced, however the object is moving
examples of moving at constant speed
car cruising on the highway at a constant speed 60km/h is balanced as there is no acceleration and the forward force from the engine is balanced by the resistive forces of air resistance and friction
define and describe speeding up (acceleration)
when an object is speeding up, it means the velocity of the object is increasing overtime. in this case the forces are unbalanced, and the net force acting on the object is in the direction of the motion
examples of speeding up
pressing the accelerator in a car speeds up a car due to the force from the engine exceeding the resistive forces
define and describe slowing down (acceleration)
when an object is slowing down it is due to the decreasing velocity of the object. here, the net force is the opposite direction to the motion
examples of slowing down
applying the brakes in a car slows down the car as the braking force overcomes the forward motion force
what is newtown’s first law
newtown’s force states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force
how do you calculate work done
force times distance
what does w=Fs mean
work done = force times distance
how do you calculate kinetic energy
1/2mv (squared) or 1/2 times mass times velocity squared
what does k=1/2mv(squared)
1/2 times mass times velocity squared
what are the particles within an atom
- protons
- neutrons
-electrons
characteristics of a proton
proton’s relative mass is 1
location: inside the nucleus so it cannot move between object
charge: positive
characteristics of a neutron
neutron’s relative mass is 1
location: inside the nucleus so it cannot move between object
charge: neutral
characteristics of a electron
electron’s relative mass is 0.0005
location: is outside the nucleus so it can move between objects
charge: negative
what happens when ebonite is rubbed against wool
the neutral ebonite rode turns into a negative charge
the neutral wool has a positive charge
what happens when perspex is rubbed against silk
the neutral perspex changes into a positive charge
the neutral silk turns into a negative charge
