Chapter 2: Chemistry Flashcards
Define matter.
Matter is defined as anything that has mass and takes up space.
Define the Particle Theory of Matter.
A model that has been developed to help us understand matter. helps us visualize how matter behaves as well as helps us to explain why different matter can display different properties.
What is matter made up of?
tiny particles, either individual atoms or groups of atoms (molecules)
What is the difference between protons and neutrons?
protons are positively charged particles and neutrons are particles with no charge.
What is the center of a atom called?
Nucleus.
What are electrons?
Negatively charge particles that orbit around the nucleus.
How is the type of atom defined?
By the number of protons in the nucleus.
What keeps the electrons orbiting around the positive charge of the nucleus?
Electrostatic force
How much heavier are protons & neutrons than electrons?
200 times heavier
What is most of the volume of a atom?
empty space
What is absolute zero (temperature)?
-273.15 degrees Celsius = 0 kelvins O K
How does speed affect the temperature of particles?
The higher the average speed, the higher the temperature.
What is the size of particles of matter?
very small, between 10 000 and 1 000 000 times smaller that the diameter of a strand of hair, you can not see them with your eyes only with sensitive instruments.
What is a subatomic particle?
Any particle smaller than an atom. Protons, Neutrons, electrons are all subatomic particles.
What are the study of subatomic particles called?
Particle Physics, Subatomic Physics, High Energy Physics.
What do scientists agree on regarding the fundamental structure of matter?
Everything in the universe is found to be made of twelve basic building blocks called FUNDAMENTAL PARTICLES. which interact with four fundamental forces.
What is the Standard model (of particles and forces)?
Theory of how particles and forces relate to each other.
What are the two basic groups of matter particles (Fermions)?
Quarks and Leptons. They each consist of 6 kinds of particles organized in pairs.
Describe the differences between Generation I II & III for the Standard Model.
Generation I - lightest most stable particles
Generation II - heavier less stable particles
Generation III - heavier less stable particles
What four fundamental forces, are the Fermions (matter particles) affected by?
Strong Force, weak force, electromagnetic force, Gravitational Force.
What are the four fundamental forces carried by?
Force carrier particles called BOZONS
What are States of Matter?
The physical form of matter.
What are the three well known states of Matter?
Solid, Liquid, Gas
What are some other states of matter?
Plasma - contains free moving electrons.
Bose-Einstein Condensates (BECs)-waves of matter that can occur with some types of atoms at super cold temperatures.
What happens when you warm up matter(add energy)
the particles start moving faster and spread apart
Describe Solids
Force is strong, articles stay close together, Particles can vibrate but they are not moving around much, this makes solids hard and rigid. Solids keep there shape.
Describe Liquids
Force is weaker, particles close together but can move around freely. Liquid can flow around inside container & don’t have a fixed shape.
Describe Gases
Force is strong enough to keep particles close together because the particles are moving very fast and have lots of energy.
What is Strong Force?
The Force that holds the protons and neutrons together to form the nucleus of an atom. Also holds the quarks together to from protons and neutrons.
What is Weak Force?
Responsible for radioactive decay and hydrogen fusion in stars. It acts on all Fermions (matter) Believed to be caused by the exchange of W and Z Bosons.
Describe Electromagnetic Force.
Force which acts on particles that are electrically charged and on metals which can be magnetized.
How is Electromagnetic Force commonly experienced in everyday life?
In the form of electric fields (which cause electric voltage and current) and magnetic fields (magnets)
Describe Gravitational Force
Gravity occurs between physical objects which attract with a force proportional to their mass. Gravitation is responsible for keeping the Earth and other planets in their orbits around the sun.
What is Graviton?
Force carrier particle for gravitation. (theory that is not yet proven)
What is ADDITIVE MANUFACTURING (AM)?
3D printing. It creates a solid object by putting down thing layers of material such as plastic and metal.
Who invented the technology for 3D printing?
Scott Crumps in the 198’s.
What is a property of matter?
Property is something that describes matter, to allow us to identify substances.
What is a physical property? Give examples
A characteristic of matter that we can measure. Color, odour, taste, size, shape, boiling point, melting point, hardness, malleability (ability to be pounded flat), electrical conductivity, magnetism and density are examples of physical properties.
What is a chemical property?
a characteristic of a substance which describes it potential to undergo a chemical reaction or change.
Give examples of Chemical Properties.
Flammability - ability to burn
Reactivity-ability to react when combined with other substance.
Corrosiveness-ability to eat away another substance
Toxicity-ability to cause damage to living organisms
Describe the difference between Intensive & Extensive property.
Intensive is a property that does not depend on the amount of matter. (color, odour, density, melting point) Extensive property is a property that depends on the amount of matter. (mass & volume)
Give examples of different ways to classify matter?
Pure substance or a mixture.
Describe Pure Substances.
Pure Substances have a fixed composition and cannot be separated into other pure pure substances by physical means. Physical properties of a pure substance never change. Elements and Compounds are pure substances.
What is an element? Give examples
Elements are substances that are made of only one type of atom. Examples are, Carbon (C), Silver (Ag) & Gold (Au).
How many know elements have been discovered?
116
What is the Periodic Table?
A table created by scientists to organized the elements graphically.
What are compounds? Give example.
Compounds are substances formed by the union of two or more elements.. The compounds are held together in a fixed ratio and can be broken down to individual elements by chemical means. Water is an example because it is a compound made up of two hydrogen atoms (H) and one oxygen atom (O)
Describe Mixtures?
Mixtures are a combination of two or more pure substances. When mixed together each pure substance retains it own properties. Can be homogeneous or heterogeneous.
What is a Homogeneous mixture? Give example
A mixture that is completely uniform in composition. Can be made of gases (air) and solids & metals such as brass (know as alloys)
An example of a Homogeneous mixture is salt water.
What is another name for Homogeneous Mixture?
A solution.
What is a heterogeneous Mixture? Give example.
A mixture that is not uniform in its composition It is a mixture in which individual components can be seen. An example is oil and vinegar salad dressing.
Name the two types of energy
Potential energy (Ep) & Kinetic Energy (Ek)
What is the total energy in a particular system?
The total energy in a particular system is the sum of the kinetic and the potential energy present.
Etotal = Ek+Ep
Describe heat.
Heat is a form of energy that is associated with the motion of atoms, molecules and other particles.
What happens as temperatures increase?
Molecular motion become faster and faster.
How can heat energy be transferred from one object to another?
As a result of an temperature difference between two objects. When a warmer object is brought into contact with a cooler one, the cooler object will get warmer until eventually the temperature between the two becomes equal.
What direction is the flow of heat energy?
The flow of heat energy is ALWAYS in the direction from a warmer body to a cooler body.
How is heat measured?
Heat is measured in Joules (J) or sometimes Calories (cal) which are the energy in food.
Name the three ways heat can be transferred.
Conduction, Convection, Thermal Radiation.
Describe Conduction.
Transfer of heat within and between materials and objects which are in direct contact with each other. Molecules at the warmer end of an object will more vibrate quickly then those at the cooler end of object. The faster moving molecules collide with the slower ones, causing them to vibrate faster.
What is Thermal Conductivity?
A property of a material which measures how well it conducts heat.
Give examples Conductors (good at conducting heat)
Metals such as silver, copper, and aluminum.
Give examples insulators(not good at conducting heat)
Styrofoam, snow, fiberglass
Describe Convection?
Convection is the movement of molecules within fluids. (liquids and gases)
How does heat transfer occur with Convection?
Heat transfer through convection occurs when the liquid or gas molecules physically move, as opposed to simply vibrate more quickly. Example heating water in a pot on a stove.
Do solids undergo Convection?
No, they mostly undergo conduction
Describe Heat transfer through Thermal Radiation?
The transfer of energy via electromagnetic (EM) wave.
Give examples of objects that can transfer heat through thermal radiation.
A hot campfire, a glowing heating element on the stove, the sun.
An example of all three transfer processes occurring at the same time is the heating/cooling of a house, DESCRIBE THIS.
Conduction- in the summer heat is transferred from the warm air outside into the house through walls or roof. In the winter heat is transferred from the warm air inside the house out through the wall or roof.
Convection-occurs inside each room as warm air rises towards the ceiling and cooler sinks towards the floor. This is also why second floors feel warmer.
Thermal Radiation- the sun heats the roof of the house and can also transfer heat energy through windows.
