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