III. Classifying Matter Flashcards
Chemistry:
the study of the composition of matter and the changes it undergoes
What are the units of matter?
Atoms and elements
Atoms:
the smallest unit of an element that maintains the chemical identity of that element.
Element:
a pure substance that cannot be broken down into simpler, stable substances and is made of only one type of atom
What is matter?
Anything that has mass and volume
Volume:
the amount of three dimensional space an object occupies
Mass:
a measure of the amount of matter
(SOLID) Volume & shape?
Definite volume and shape
(SOLID) Arrangement?
packed close together
(SOLID) Movement?
Vibrate in a fixed position
(SOLID) Attractive Forces/ energy?
Very strong force of attraction
Low energy
(LIQUID) Volume & shape?
Definite volume
NO definite shape
(LIQUID) Arrangement?
Close together, but can slide past one another
(LIQUID) Movement?
Move past one another, Slide Flow
(LIQUID) Attractive forces/ energy?
Strong force of attraction
Medium energy
(GAS) volume & shape?
No definite volume/shape
(GAS) Arrangement?
Spread out as far apart as possible
(GAS) Movement?
Move with great speed
(GAS) Attractive forces/energy?
Very weak force of attraction
Very high energy
Two classes of Matter:
pure substance and mixtures
Pure substance:
has a fixed position composed of just one type of particle (atom or molecule)
Pure substances are either what?
compounds or elements
Elements:
the simplest pure substance
can’t be broken down into smaller substances by ordinary means
made up of only one type of atom
Compounds:
A pure substance- definite composition
Two or more elements combined through a chemical reaction
Composed of a definite group of molecules or ions that are chemically bonded
Mixture:
A physical combination of two or more substances
Identities and properties of the individual substances are retained
Can be separated by physical means
The chemical and physical properties of a compound _______from those of the elements that make up the compound.
Differ
Difference between compounds and mixtures
- Compound has one set of properties that are diff than the properties of the elements that make up the compound
- In a mixture, substances that make up the mixture retain of their properties (ex. salt water)
-compounds => definite composition - a formula - Mixtures => no definite composition - varies
Types of Mixtures
Homogeneous and heterogeneous
Heterogeneous Mixture:
- does not appear to be the same throughout
- particles large enough to see and separate from mixture
- can see diff substances
ex. oil and water
Homogeneous Mixture:
- a mixture that appears to be the same throughout
- particles do not settle out when left standing
ex. air (a solution of nitrogen, oxygen, argon, carbon, etc)
A homogeneous Mixture also called a…
A solution
