science Flashcards
what are the three states of matter
solids, liquids and gases
what is shape change
the substance is altered to be shaped differently
what is mixing
combinig two substances together
what is dissolving
placing a solute and a solvent
what is a solute
A solute is a substance that can be dissolved into a solution by a solvent
what is a solvent
a solvent is the substance in which a solute dissolves to produce a homogeneous mixture.
what is expansion
heat causes the substance to expand
what is contraction
cold causes the substance to shrink
what is melting
heating a solid until it becomes a liquid
vaporisation
heating a liquid until it becomes gas
condensation
cooling a gas until it becomes a liquid
freezing
cooling a liquid until it becomes a solid
what are atoms
Inside an atom there are subatomic particles called:
* Electrons (negatively charged) - these move around the outside of the nucleus
* Protons (positively charged)
* Neutrons (neutral)
what are molecules
molecules are two or more atoms bonded to create a molecule
what are elements
An element is any substance made up entirely of one particular type of atom – the basic building blocks of stuff. We know that elements have three ingredients: protons, neutrons, and electrons.
solidifying
changing a liquid to solid
sublimation
changing a solid to a gas
deposition
changing gas to a solid
what is diffusion
example: if someone opens a bottle of perfume in the middle of the room, you soon smell it in other parts of the room
controlled variable
a controlled variable is something that stays the same
dependent variable
a dependent variable is something that can be measured
independent variable
an independent variable is something that purposely changes.
WHAT IS DENSITY !!!!!!!!!!
density is how much mass is packed into a measured volume
density (g/cm3) = mass (g)/ volume (cm3)
what is matter
- Everything is made of matter
- Matter is anything that takes up space and has mass
- ‘Matter’ comes from the Latin root meaning “stuff”
what is a physical change
the appearance or form of the matter changes but the kind of matter in the substance does not.
what is a chemical change
In A chemical change atoms in the molecules change to form different combinations of atoms (new substances)
A chemical equation is
reactant + reactant - product + product
Reactant – substance/s you start with
Product – substance/s you end up with
