Elements, Compounds, & Mixtures

• Objectives• Describe pure substances• Describe the characteristics of elements,

and give examples• Explain how elements can be identified• Classify elements according to their

properties

Section 1: Elements

3.1 Elements• Element- A ________ _______ that cannot be

separated into simpler substances by chemical or physical means.

• Pure Substance- A substance in which there is only ____ type of particles

Properties of Elements• Each element has its own characteristic properties.

• These include boiling/melting point, _______, reactivity, _____________, etc.

• An element may share one or two ____________ with another element, but it will not share all its properties with another element. There will be ________ properties for each element.

Classifying Elements

• You can use properties to identify elements. • Think about how many types of dogs there are.

• How do you tell one breed from another?

• Categories of Elements• Metals• ______________• ______________

Classifying Elements• Metal- an element that is _____ and conducts _______ and

electricity well

• Properties• ___________ – ability to be hammered

into sheets• Ductile – ability to be drawn into

wires

Classifying Elements

• __________ – an element that conducts heat and electric poorly• Properties

• 1. ____________• 2. brittle – not malleable

• Metalloid- an element that has properties of metals and _______________• Properties

1.some are shiny2. some are dull3. somewhat malleable and ductile4. some are good conductors of heat and electricity

5. some are poor conductors of heat and electricity

Classifying Elements

Classifying Elements  Appearance Conductivity Physically Example

 _________  

  Shiny

 ________

 malleable., ductile

 Lead, Copper

 Nonmetal  

  Dull

 ________

 Brittle

 Sulfur, oxygen

  Metalloid 

 Some Shiny/ some dull

 Some good/ some poor

 Somewhat malleable and ductile

 ________, ________

• Section Review• Please answer the objectives on your summary sheet

1. Describe pure substances

2. Describe the characteristics of elements, and give examples

3. Explain how elements can be identified

4. Classify elements according to their properties

Section 1: Elements

• Objectives• Explain how elements make up compounds• Describe the properties of compounds• Explain how a compound can be broken down

into its elements• Give examples of common compounds

Section 2: Compounds

3.2 Compounds• Compound- a substance made up of atoms of _____ or

more different elements joined by __________ ______• Examples: H2O (water), NaCl (table salt)

• A particle of a compound is called a ___________ • Elements do not randomly combine. They join into a specific

_______ according to their masses.

• Properties Compounds versus Elements• A compound will have different

______________ than the elements that make it up

Section 2: Compounds

Compounds

Sodium• Soft• Silvery, white metal• Reacts violently with

Chlorine Gas Poisonous Greenish-yellow

But when chemically combined…

You get……..

NaCl = _______________

Breaking Down Compounds• Some compounds can be broken down into their elements or

simpler compounds by _____________ means. • Sometimes energy in the form of _______ is needed to do

this.

• Section Review• Please answer the objectives on your summary sheet

1. Explain how elements make up compounds

2. Describe the properties of compounds

3. Explain how a compound can be broken down into its elements

4. Give examples of common compounds

Section 2: Compounds

• Objectives• Describe three properties of mixtures• Describe methods of separating the parts of a mixture• Analyze a solution in terms of its solute and solvent• Describe factors that affect solubility for solids, liquids, and

gases• Explain how concentration affects a solution

• Describe the particles in a solution, suspension, and colloid

• Explain the difference between colloids, solutions, and suspensions

Section 3: Mixtures

3.3 Mixtures• Mixture- A combination of two or more substances that are

not ____________ combined.• An example would be a salad (or salsa as in the picture). The

cheese, sauce, and dough are still the same items after you make the pizza.

Properties of Mixtures• Sometimes you cannot see all the components like in salt

water This is called a ____________ mixture. It includes salt and water.• Since mixtures are not chemically combined, you can separate

the different substances by ___________ methods. • Components in a mixture do not need to be in a specific ratio.

Sometimes you can just pick ingredients out of a mixture (pizza)This is called a _______________ mixture

Separating Mixtures Other ways to separate mixtures include:

evaporation – separates a mixture based on boiling points Ex: salt in water

• ___________ - a process to separate materials based on their size. Ex: coffee filters and a screen to find artifacts at a historical site.__________ – separates a mixture based on density.

Ex: crude oil – gasoline & propane

centrifuge – separates based on particle size Ex: blood

Compounds vs. mixtures

_____________ ______________ Made of elements, compounds or

bothMade of elements

No change in original properties of components

Change in original properties of components

Separated by physical means ______________________________

Formed by using any ratio of components

Formed using a set ratio of components

Mixture vs. compound vs. element

Solutions, Suspensions, & Colloids

Solutions• __________ - A mixture that appears to be a single substance.

• Particles are small & cannot be ____________• Solutions have the same _______________ throughout.• Example: Salt Water

• ___________ - Substance that is dissolved. (Salt)• Solvent- The substance in which the solute is dissolved. (water)

Hide the LOOT in the VENT!

Solutions Continued• The term soluble means able to __________. Insoluble means

unable to dissolve.• Solutions can be solids, liquids, or gases.

• __________- Measure of the amount of solute dissolved in a solvent. • This is expressed as g/mL• To increase solubility:

• _________• stir• crush – smaller particles

• How does temperature affect solubility?• For liquid solvents

• A higher temperature makes a gas _______ soluble• A higher temperature makes a solid _______ soluble

• USUALLY

• A higher temperature makes a liquid more soluble

Section 3: Mixtures

• To get solids to dissolve faster…Section 3: Mixtures

___________________________- Causes particles to separate and spread out faster

_____________- Causes particles to move more quickly and separate

________________- Spreads out solute to mix with solvent more quickly

Colloids• _________ A type of mixture in which the particles are

dispersed throughout but are not heavy enough to settle out• Particle size is larger than that of a solution but small enough

they will still pass through a filter.• Examples of colloids: _________, fog

Colloids Colloids scatter _________. (fog) You can actually see the beam of

light in the colloid.

Suspensions• Suspensions- A mixture in which the particles of a material are

dispersed throughout a liquid or gas but are ______ enough that they settle out.• Particles are large enough to settle out.• Suspensions can be separated by passing through a _________.• Examples: Italian salad dressing, muddy water

Elements, Compounds, Mixtures

Elements _____________ Mixtures

How many parts make it up?

1 2 or more 2 or more elements or compounds

Pure: more than one substance?

pure pure _______________

Chemically or physically combined?

__________ ______________ _______________

Chemical change to make them?

N/A Yes no

Fixed ratio? N/A Yes no

How separated: chemically/physically?

N/A Chemically physically

• Section Review• Please answer the objectives on your summary sheet

1. Describe three properties of mixtures2. Describe methods of separating the parts of a mixture3. Analyze a solution in terms of its solute and solvent4. Describe factors that affect solubility for solids, liquids, and

gases5. Explain how concentration affects a solution6. Describe the particles in a solution, suspension, and colloid7. Explain the difference between colloids, solutions, and

suspensions

Section 3: Mixtures