Chapter 1: Matter, Energy, and Measurement
● Chemistry- Study of matter, its properties, and the changes it undergoes
● Matter- Anything that has mass and takes up space
○ Atoms & Molecules
● Classification of matter based on composition
○ Homogeneous mixture- Mixture that looks the same throughout; you can’t see
the different parts
■ Also called a solution
○ Heterogeneous mixture- Mixture where you can see the different parts; not
uniform
○ Element- Pure substance made of only one kind of atom
○ Compound- Pure substance made of two or more elements chemically bonded
together
● Law of Constant Composition (or Law of Definite Proportions)
○ A given chemical compound always contains the same elements combined in the
same proportions by mass, regardless of its source or how it was prepared
● Physical properties
○ Can be observed without changing a substance into another substance
■ Color, melting point, and density
● Chemical Properties
○ Only observed when a substance is changed into another substance
■ Reactivity with water or acids, flammability
● Intensive properties are independent of the amount of the substance that is present.
● Extensive properties depend upon the amount of the substance present
● Physical Changes- changes that do not change the composition of a substance
○ Changes of state, temperature, and volume
● Chemical Changes- result in new substances.
○ Combustion, oxidation, and decomp
● Mixtures can be separated based on physical properties of the components of the
mixture
○ Distillation, filtration, chromatography
● Energy- capacity to do work or transfer heat
● Work- Energy needed to move against a force
,SI Units
Pure substance: only contains one specific element or compound
Chapter 1 Summary
I. Matter
Structure
→ Atom = Nucleus (Protons + Neutrons) + Electrons
, → Molecule = Two or more atoms bonded together
→ Types of Molecules:
● Element: Only 1 kind of atom (e.g. H₂, O₂, N₂, Fe, Na)
● Metals: exist as single atoms
● Nonmetals: can be atoms (H) or diatomic molecules (H₂)
● Compound: 2+ different atoms (e.g. H₂O, CO₂, Fe₂O₃)
Mixtures
● Homogeneous (solution): uniform composition (e.g. air, saltwater)
● Heterogeneous: non-uniform (e.g. salad, sandy water)
II. Properties
● Physical Properties (no chemical change): color, mass, melting point, etc.
● Chemical Properties (observed during a reaction): flammability, reactivity, decomposition
Types of Properties:
● Intensive (independent of amount): density, color
● Extensive (dependent on amount): mass, volume
Tip: Intensive = Inside (nature), Extensive = External (amount)
III. Methods to Separate Mixtures
● Filtration: separates solid from liquid
● Distillation: separates based on boiling points
● Chromatography: separates by adherence to surfaces
IV. Energy
● Energy = the capacity to do work or transfer heat
● Kinetic Energy: energy of motion. KE = ½mv^2
● Potential Energy: stored energy (relative position of objects)
VII. Units
SI system Metric System
Length Meter (m) Meter
Mass Kilograms (kg) Gram (g)
Temperature Kelvin (K) Kelvin or Celsius (C)
Time Seconds (s) Second
● Chemistry- Study of matter, its properties, and the changes it undergoes
● Matter- Anything that has mass and takes up space
○ Atoms & Molecules
● Classification of matter based on composition
○ Homogeneous mixture- Mixture that looks the same throughout; you can’t see
the different parts
■ Also called a solution
○ Heterogeneous mixture- Mixture where you can see the different parts; not
uniform
○ Element- Pure substance made of only one kind of atom
○ Compound- Pure substance made of two or more elements chemically bonded
together
● Law of Constant Composition (or Law of Definite Proportions)
○ A given chemical compound always contains the same elements combined in the
same proportions by mass, regardless of its source or how it was prepared
● Physical properties
○ Can be observed without changing a substance into another substance
■ Color, melting point, and density
● Chemical Properties
○ Only observed when a substance is changed into another substance
■ Reactivity with water or acids, flammability
● Intensive properties are independent of the amount of the substance that is present.
● Extensive properties depend upon the amount of the substance present
● Physical Changes- changes that do not change the composition of a substance
○ Changes of state, temperature, and volume
● Chemical Changes- result in new substances.
○ Combustion, oxidation, and decomp
● Mixtures can be separated based on physical properties of the components of the
mixture
○ Distillation, filtration, chromatography
● Energy- capacity to do work or transfer heat
● Work- Energy needed to move against a force
,SI Units
Pure substance: only contains one specific element or compound
Chapter 1 Summary
I. Matter
Structure
→ Atom = Nucleus (Protons + Neutrons) + Electrons
, → Molecule = Two or more atoms bonded together
→ Types of Molecules:
● Element: Only 1 kind of atom (e.g. H₂, O₂, N₂, Fe, Na)
● Metals: exist as single atoms
● Nonmetals: can be atoms (H) or diatomic molecules (H₂)
● Compound: 2+ different atoms (e.g. H₂O, CO₂, Fe₂O₃)
Mixtures
● Homogeneous (solution): uniform composition (e.g. air, saltwater)
● Heterogeneous: non-uniform (e.g. salad, sandy water)
II. Properties
● Physical Properties (no chemical change): color, mass, melting point, etc.
● Chemical Properties (observed during a reaction): flammability, reactivity, decomposition
Types of Properties:
● Intensive (independent of amount): density, color
● Extensive (dependent on amount): mass, volume
Tip: Intensive = Inside (nature), Extensive = External (amount)
III. Methods to Separate Mixtures
● Filtration: separates solid from liquid
● Distillation: separates based on boiling points
● Chromatography: separates by adherence to surfaces
IV. Energy
● Energy = the capacity to do work or transfer heat
● Kinetic Energy: energy of motion. KE = ½mv^2
● Potential Energy: stored energy (relative position of objects)
VII. Units
SI system Metric System
Length Meter (m) Meter
Mass Kilograms (kg) Gram (g)
Temperature Kelvin (K) Kelvin or Celsius (C)
Time Seconds (s) Second
