Matter and Energy
Chemical Change
- A new substance is formed from the change - atoms break apart and form different to form different atom groups - attraction energy different in different molecules - takes more energy to occur than a physical change - in general not as easily reversible - clues that a chemical change is occurring: fizzing, change in temp, light emission, new odor or a color change (some can also occur in physical changes)
Atoms
- Atoms are forever, no matter the chemical or physical changes - energy can't change into atoms - all of the substances on Earth are made of tiny tiny tiny particles called atoms - can't see them with a microscope - 100 different kinds of atoms - building blocks of the universe - EX: Carbon, hydrogen etc.. - Atoms is the smallest particle making up an element - almost always connected in groups - naturally occurring or human made, all made from the same 100 building blocks.
Physical Properties
- Determined by molecular level behavior - all objects and substances have a unique set of physical properties which is determined by the composition of the substance, those properties are what make a substance and the substance what it is. - you can out objects into groups based on a common property they share different physical properties of matter make specific objects and substances useful for people - determined by the type of atom group that makes up a substance
Matter
- all the objects and substances you can think of - anything that has mass and takes up space (has volume) - matter has mass (how much stuff makes up the substance, regardless of how much space it takes up) - weight is an indirect measure of how much matter there is making up a substance -matter is anything that has weight/mass and volume - characteristics: motion, position and composition
Molecule
- atoms are attracted to some other atoms and end up forming a little atom group - atom groups can be composed of the same type of atoms -like oxygen or different types like water --> hydrogen and oxygen - atom groups can range in size from two atoms to millions -NOT THE ATOM THAT DETERMINES THE SUBSTANCE, THE ATOM GROUP DOES. - even if the ending matter is different in motion and temp. but the atoms all still exist and they're even in the same atom groups - determined by both they type of atom and number of atoms involved - have energy of attraction for other molecules, never changes, depends on the atoms within each of the molecules
Gasses
- do not have a definite shape or definite volume - their shape and volume depend on the container they are in -you can compress a gas into a smaller space - the pushing away force win over the pulling together force big time - INDEFINITE SHAPE AND VOLUME
Energy
- doesn't have mass or take up space - EX: Can't fill a cup with sound energy - Different forms (conversion) an initial form can become more than one form, heat is always involved - what changes matter - can still be quantified, all units can be converted to each other - can change its location/move and get transfered - never created or destroyed, have exact same after as before - if it appears there is less, some is transfered into heat energy and spread out in the environment
States of Matter
- each of the states of matter can be explained by the behavior of the molecules - the mass of a given substance or object doesn't change in the three states - energy is involved for changes (heat given or taken away) - changes of state, molecule have a big enough change in the amount of their thermal energy that their type of arrangement changes, which leads to a change in their type of motion (move faster or slower)
Solids
- have a definite or unchanging shape and volume as long as you're not transferring energy to or from it - molecules packed together and locked in position - the pull is stronger than the push - SOLID HAS A DEFINITE SHAPE AND VOLUME
Liquids
- have a definite volume but not a definite shape - they take the shape of the container they are in - push away harder when they hit other molecules - the greater pushing force works against the pulling force of the attraction between molecules - they not packed tight - LIQUIDS HAVE A DEFINITE VOLUME AND INDEFINTE SHAPE.
Density
- how much matter there is given volume of an object - the relationship between the mass and the volume of an object is expressed as a fraction - the mass of the object divided by the volume of the object - unit for mass is grams and unit for volume is milliliters
Evaporate
- molecules at the surface of the liquid gain enough energy to break away front heir attraction to each other liquid --> gas
Mass
- the mass of any substance comes from the collective mass of all its tiny atoms, the mass depends on the atoms that make it up. - all substance are made up of atoms, each tiny tiny atom has a tiny tiny bit of mass - different types of atoms has different masses, but nevertheless, they are all still have very small amounts of mass - Each atom contribute its tiny amount of mass to the overall total mass of a substance - the mass and amount of matter remains constant (conservation of mass) - mass depends on the number and type of atoms that make it up - WHEN ATOMS REMAIN CONSTANT, MASS REMAINS CONSTANT - if mass is less, it is in a different location, the air, it isn't destroyed or disappeared. - If it's more, they were in a different place, existing somewhere else, and have now changed forms to join the object.
Thermal Contraction
- when a substance decreases volume due to subtraction of heat energy - solid and liquid don't have definite volume
Physical Changes
-an object changing a physical property - can be explain in terms of the molecules that make up the substance - any physical property of a substance or object can be changed with energy - remain the same substance throughout
Mixture
-combinations of two or more substances with each substance keeping its own properties when the substances are mixed together - the components of mixtures can be separated by using the different physical properties of each component
Loners
-exceptions to these two types of atom groups - the elements whose atoms aren't attracted at all to other atoms, not even to the atoms of themselves - they don't form an atom group at all, they wander around eh universe unpaired and unattracted.
Thermal Expansion
-when a substance gets bigger due to the addition of heat energy - the substance's molecules doesn't expand, the space between them does, causing increased volume - solid and liquid don't have definite volume
Energy Change
1) energy units can move from one place or object to another 2) energy units can change from one form to another
Matter Change
1) the atom groups making up a substance can change in motion and or arrangement but keep the same composition and stay in the same place 2) the atom groups making up a substance can break apart and the atoms form new atom groups which make new substances 3) the atom groups as a whole can change in location with the composition and spacing of atom groups staying the same
Electrical Energy
energy of moving electrons
Thermal Energy
energy of moving molecules, can transfer to nearby molecules in the environment
Mechanical Energy
energy of moving objects
Chemical Energy
energy of separated atoms that are attracted to each other
Gravitational Energy
energy of separated objects that are attracted to each other
Light Energy
energy of vibrating electrons
Sound Energy
energy of vibrating objects
New Substances
it is of the same starting and ending atoms, just different formations after they break apart and reform into a new substance
Solidify
liquid --> solid
Boiling
liquid changes to a gas suddenly
Compund
molecules that consist of different types of atoms
Elements
one type of atom
Elastic Energy
stretched or compressed parts of an object
Pure Substance
substances that are made up of just one kind of matter
Shape
the specific 3D form of a substance volume
Law of Conservation of Matter
there is the same number and type of atoms before and after a chemical change, the total mass of all the substances will be the same before and after.
Describing a subject/object
think of its physical properties, its motion and position and composition (the type of molecules that make it up)
Chemical Properties
those that involve how the matter reacts with other types of matter, including reacting to acids and reacting with oxygen.
Grouping
you can put the objects into groups based on common property they share