INTRO TO CHEMISTRY

aspirin sucrose

Matter – types and properties of

• Chemistry is the science that investigates and explains the structure and properties of matter.

Composition, Structure, and Behavior

Chemistry and Matter: Basic Concepts Chemistry and Matter: Basic Concepts

Composition, Structure, and Behavior

Chemistry and Matter: Basic Concepts Chemistry and Matter: Basic Concepts

• Matter is the stuff that’s all around you: the metal and plastic of a telephone, the paper and ink of a book, the glass and liquid of a bottle of soda

Composition, Structure, and Behavior

Chemistry and Matter: Basic Concepts Chemistry and Matter: Basic Concepts

• Matter is the stuff that’s all around you: the air you breathe, and the materials that make up your body.

Composition, Structure, and Behavior

Chemistry and Matter: Basic Concepts Chemistry and Matter: Basic Concepts

• A more formal definition of matter is anything that takes up space and has mass.

• Mass is the measure of the amount of matter that an object contains.

• The structure of matter refers to its composition - what matter is made of - as well as how matter is organized.

• The properties of matter describe the characteristics and behavior of matter, including the changes that matter undergoes.

• A powerful way to classify matter is by its composition. This is the broadest type of classification.

Classification of Matter by Composition

• A qualitative observation is one that can be made without measurement.

• When you examine an unknown piece of stuff, you first ask, “What is it made of?”

• Sucrose is composed of the elements carbon, hydrogen, and oxygen. This is a qualitative expression of composition.

• After a qualitative analysis, the next question that you might ask is how much of each of the elements is present.

Classification by Composition

• A quantitative observation is one that uses measurement.

• For sucrose, the answer to that question is that 100 g of sucrose contains 42.1 g of carbon, 51.4 g of oxygen, and 6.5 g of hydrogen. This is a quantitative expression of composition.

Pure substance or a mixture?

• A sample of matter is either ;

pure - made up of only one kind of matter

or

Pure substance or a mixture?

• A sample of matter is either ;

pure—made up of only one kind of matter

or mixture – made of two or more different kinds of matter. The basic identity of each

substance is not

changed

Pure substance or a mixture?

• A substance is matter, either an element or compound, with the same fixed composition and properties.

• A sample of matter is either ; pure

or mixture

Two Types of Substances

• Compounds - can be broken down into simpler substances.

Two Types of Substances

• Element - cannot be broken down into simpler substances

Two Types of Substances

• All the substances of the universe are either elements, compounds formed from elements, or mixtures of elements and compounds.

Compounds - can be broken down into simpler substances.

Element – cannot be broken down into simpler substances

• A physical change is a change in matter that does not involve a change in the chemical identity of individual substances.

• A physical change is a change in matter that does not involve a change in the chemical identity of individual substances.

• Examples of physical changes include:

• boiling • evaporating

• dissolving

• crystallizing

Can you think of more examples?

• Physical properties are characteristics that a sample of matter exhibits without any change in its identity.

• Physical properties are characteristics that a sample of matter exhibits without any change in its identity.

Examples of the physical properties of a chunk of matter include its• Solubility – ability to dissolve in a liquid• melting point

• boiling point• color• density

• electrical conductivity• physical state (solid, liquid, or gas)

• Physical properties examples.

Solubility physical state

boiling pointcolor

Chemical Properties

• Chemical properties are those that can be observed only when there is a change in the composition of the substance.

Chemical Properties• Chemical properties are those

that can be observed only when there is a change in the composition of the substance.

• Rusting is a chemical reaction in which iron combines with oxygen to form a new substance, iron oxide.

Chemical Properties

• Chemical properties are those that can be observed only when there is a change in the composition of the substance.

• Rusting is a chemical reaction in which iron combines with oxygen to form a new substance, iron oxide. • Inability to react is also a chemical property.

Basic Assessment QuestionsBasic Assessment QuestionsQuestion 1

Identify each of the following as either a compound or a mixture.A. sand

B. water

C. juice

Basic Assessment QuestionsBasic Assessment QuestionsAnswers

A. sand

B. water

C. juice

mixture

compound

mixture

Basic Assessment QuestionsBasic Assessment Questions

Classify each of the following as a chemical or physical property.

Question 2

A. density

B. reactivity

C. color

D. melting point

Basic Assessment QuestionsBasic Assessment Questions

Answers

A. density

B. reactivity

C. color

D. melting point

physical property

chemical property

physical property

physical property

A farmer compares how his crops grow with and without phosphorous fertilizers.

independent variable:

dependent variable:

Question 3

Assessment QuestionsAssessment Questions

A farmer compares how his crops grow with and without phosphorous fertilizers.

independent variable: presence of phosphorous fertilizer

dependent variable: crop growth

Question 3

Assessment QuestionsAssessment Questions

A student tests the ability of a given chemical to dissolve in water at three different temperatures. independent variable: dependent variable:

Question 4Assessment QuestionsAssessment Questions

A student tests the ability of a given chemical to dissolve in water at three different temperatures. independent variable: temperature dependent variable: ability to dissolve in water

Question 4Assessment QuestionsAssessment Questions