chapter 2. learn about the composition of matter learn the difference between elements and...
TRANSCRIPT
Chapter 2
Learn about the composition of matter
Learn the difference between elements and compounds
Learn to distinguish between physical and chemical properties and changes
Learn to distinguish between mixtures and pure substances
Learn to methods of separating mixtures
Can exist in three states – solid, liquid and gas
Can be described in terms of its physical and chemical properties
Matter
Mixture
SubstanceCompound
Element
Heterogeneous
Homogeneous
Suspension
Colloid
Solution
Classification of Matter
Read Chapter 2 Answer the Focus questions at the end of
selected Sections (pages 29 & 41)
Atoms – tiny particles that make up matter
Elements are made of atoms No two elements are made of the same
atoms Made of one type of atom
Compounds are made of molecules that are made of two or more different atoms bonded together A specific compound consists of the same
particles throughout Molecules are made of atoms that are “stuck”
together bonded. CO2 Always have the same composition same
combination of atoms.
1. Oxygen2. Carbon3. Carbon monoxide4. Sugar5. nylon
1. Copper wire2. Silver nitrate3. Lead4. Salt5. Magnesium strips
Describe a substance’s ability to undergo a change to a different substance
Are the characteristics a substance exhibits as long as no chemical change occurs.
Involves a change in one or more physical properties, but no change in composition.
The most common physical changes are changes of state: solid liquid gas
Transforms a substance into a new substance or substances
Involves a change in the fundamental components of the substance A given substance changes into a different
substance or substances Are called reactions
Ex. Silver tarnished by reacting with substances in the air
Ex. A plant form a leaf by combining various substances from the air and soil
Has variable composition Homogeneous mixture (solution)
Has the same properties throughout Ex. tea, sugar water, glass, alloys
Heterogeneous mixture Does not have the same properties
throughout Ex. granite, salt & pepper, Italian
dressing
Two typesElements
Which cannot be broken down chemically into simpler substances
Composed of tiny particles called atoms. Each element has a characteristic type of
atom. All elements are on the Periodic table of
elementsCompounds
Which can be broken down chemically into elements
Are composed of different types of atoms. Contain molecules particles that are
composed of atoms bonded to one another Ex. Sugar, gasoline, baking soda, plastics