science topic 1-3 Flashcards
heterogeneous
The different substances that make up the mixture are visible. ex.soil
pure substance
a material that con-
tains only one kind of particle
homogeneous
The different substances that make it up are not separately visible. One substance is dissolved in another.ex. sugar in hot cofee
suspension
A cloudy mixture in which tiny particles of one substances are held within another.ex. orange juice with pulp, they can be sepreated through filter.
colloids
A cloudy mixture in which the particles of the suspended substance are so small that they cannot be easily separated out from the other substance.
ex.milk
elements
s a pure substance made up of only one type of particle, or atom. block,hydrogen,oxygen, helium
compound
When two or more elements combine chemically ex. hydrogen and oxygen to create water.
physical properties
Any property that can be observed or measured without forming a new substance. ex. texture
chemical properties
The way substances react with other substances.
physical change and example
A substance changes in form but not in chemical way ex. paper crumbling
chemical change and example
Causes one or more new substances to be formed.
ex.burning paper
Law of Conservation of Mass
In any chemical reaction, the total mass of the new substances is always the same as the total mass of the original substances.
Law of Definite Composition
Compounds are pure substances that contain two or more elements combined together in fixed (or definite) proportions
neutrons
uncharged particles in the
atomic nucleus
electrons
negatively charged
particles
