TEMPERATURE, ACIDS, BASES, MIXTURES
Review Session 3
Properties of Matter
Some are specific to only one substance
This is a characteristic property
Density, Boiling Point, Melting Point
Some can be shared by a lot of substances
This is a non-characteristic property
Mass, Volume, Temperature, acidity, alkalinity
Temperature
Def: degree of agitation of particles
How much the particles move
More energy = more movement = higher temperature
Unit used for temperature: Celsius (°C)
Acidity and Alkalinity
Acidity: The level of an acid in a substance
Alkalinity: The level of a base in a substance
Acids and bases are measured on the pH scale
Acidity and Alkalinity
Reaction to Litmus ** (Extremely Important!)
Red litmus Blue Litmus
Presence of an Acid
Stays red Turns red
Presence of a Base
Turns blue Stays blue
Presence of a Neutral Substance
Stays red Stays blue
Liquid A is a
Liquid B is a
Liquid C is a
Typical Exam Question
Which of the following is a non-characteristic property?
a) Density
b) Boiling point
c) Temperature
d) Freezing point
Typical Exam Question
Which of the following is a characteristic property?
a) Acidity
b) Boiling point
c) Temperature
d) Alkilinity
Typical Exam Question
You have a substance with a pH of 8. The substance is therefore a
a) Acid
b) Base
c) Neutral
d) None of the above
Typical Exam Question
You have a substance with a pH of 7. The substance is therefore a
a) Acid
b) Base
c) Neutral
d) None of the above
Typical Exam Question
You have a substance with a pH of 2. The substance is therefore a
a) Acid
b) Base
c) Neutral
d) None of the above
Typical Exam Question
Ms Di Lallo has a unknown liquid. She puts red litmus paper in it and the paper stays red. She puts blue litmus paper in it and the paper turns red. What is the unknown?
a) An acid
b) A Base
c) A Neutral substance
d) No idea, Ms Di Lallo needs to do another test
Typical Exam Question
Ms Di Lallo has a unknown liquid. She puts blue litmus paper in it and it stays blue. She doesn’t have any red litmus paper. What substance could it be?
a) An acid
b) A Base
c) A Neutral substance
d) Either a base or neutral; need to do another test
Types of Mixtures
Pure substance
Only one type of particle
Mixture
Two or more particles; but they are not chemically bound
Homogeneous Heterogeneous
Soluble vs Insoluble
Soluble
Dissolves in water
Ex: Salt and water, sugar and water
Insoluble
Does not dissolve in water
Ex: Mud and water, pepper and water
Typical Exam Questions
Pure gold (solid made only of the element gold) is an example of what
a) Pure substance
b) Homogeneous mixture
c) Heterogeneous mixture
d) Money
Typical Exam Questions
Lemonade; made from mostly sugar and water, is an example of a
a) Pure substance
b) Homogeneous mixture
c) Heterogeneous mixture
d) Money
Typical Exam Questions
Sand, made from different types of rocks broken into little pieces, is an example of a
a) Pure substance
b) Homogeneous mixture
c) Heterogeneous mixture
d) Money
Separation Techniques
Heterogeneous Mixtures Homogeneous Mixtures
Sedimentation: Let particles separate; heavier one settles to bottom
Decantation (done usually after sedimentation): Pour top layer into a different container, leave sedimentbehind
Filtration: Use a physical barrier(filter paper) to separate particles. Filtrate goes through filter, residuegets trapped
Distillation• Uses evaporation to boil liquid
component• Uses condensation to convert gas
back into liquid• Residue remains in original beaker
Sedimentation
Decantation
Filtration
Distillation
Typical Exam Questions
To separate sand from water, what separation technique would you use?
a) Sedimentation
b) Decantation
c) Filtration
d) Both a and b
Typical Exam Questions
To separate oil from water, what separation technique would you use?
a) Sedimentation
b) Decantation
c) Filtration
d) Both a and b
Typical Exam Questions
To separate pepper from water, what separation technique would you use?
a) Sedimentation
b) Decantation
c) Filtration
d) Distillation
Typical Exam Questions
To separate salt from water, what separation technique would you use?
a) Sedimentation
b) Decantation
c) Filtration
d) Distillation