Do Now: Brain Teasers

1) A woman from Washington married twenty different men from that city, yet she was not arrested for breaking the law. The most surprising fact is that she never divorced and none of these men died. How was this possible?

2) Can you guess the next three letters in the following series and why?C Y G T N T L I T F.........

3) What can you hold without ever touching or using your hands?

S, A, W …. Each letter is the first letter of every word in the Sentence.

She was a Justice of the Peace.

Your Breath

Announcements

Homework:

Achieve 3000 – due on March 25Give up Oil? Not so Fast! A new Space Plan

Finish Compound Concept map

Chapter 16 Vocabulary – Word+definition+picture

Science Spot Light

• Pressure Review

Classroom Objective

• Title: Elements, atoms, and compounds

• L.O. Students will understand what atoms, elements, and compounds are and how they are related. (Notes)

Review• State of Matter can be used to describe

physical properties. For example, water can be a solid (ice) or a liquid (liquid water), or a gas (evaporation).

Review• A chemical property of iron is that

it will slowly combine with oxygen in the air to form a different substance, rust.

Elements• What is an Element?

• An element is a pure substance that cannot be broken down into any other substances by chemical or physical means.

• Elements are the simplest substances.

Atoms• What is an Atom?

• An atom is the basic particle from which all elements are made.

• Atoms have a positive center (nucleus) surrounded by a negatively charged cloud.

When Atoms Combine

• Atoms of most elements have the ability to combine with other atoms.

• Atoms combine to form larger particles called molecules - groups of two or more atoms held together by chemical bonds.

• A Chemical bond is a force of attraction between two atoms.

Molecule Example• For example think of the atoms hydrogen (H) and

oxygen (O).

• Alone, the are colorless, odorless, gasses.

• When combined, they form a water molecule.

H O

O

HH

H₂O

Concept Maps

ElementOxygen

O

Atom

Positive NucleusNegative electron

cloud

+

Atom

Positive Nucleus

Negative electron

cloud

MoleculeOxygen Molecule

O₂

ElementOxygen

O

Compounds• Most elements in nature are found

combined to other elements.

• A compound is a pure substance made of two or more different elements chemically combined in a set ratio.

• A compound may be represented by a chemical formula, which shows the elements in the compound and the ratio of atoms.

• For example: H₂O The ratio of hydrogen atoms to oxygen atoms is 2 to 1.

Compounds• When elements are chemically combined, they form

compounds having properties that are different from those of the uncombined elements.

• For example:

•Calcium (solid) + Carbon (solid) + Oxygen (gas)

•= Calcium Carbonate

Concept Maps

ElementCa

Atom

Positive NucleusNegative electron

cloud

+

Atom

Positive Nucleus

Negative electron

cloud

CompoundCalcium

CarbonateCaCO3

ElementC

ElementO3+

Atom

Positive Nucleus

Negative electron

cloud

Video – Snails

• Compounds

In your notebook• Concept Map Summary

•Draw a concept map that relates atoms, elements, and molecules (or compounds).

•Include the definitions for elements, atoms, molecules, and compounds.

•Include a picture sketch or description of your molecule (or compound)

•Example: Calcium Carbonate