Chapter 2, Section 1

Elements and Compounds

Date:HW: 2.1 CTG, pg. 109 #1-4

• LO:– Explain matter– Explain the differences between elements

and compounds

• SC:– Decompose water by electrolysis into the

two elements from which it is composed– Test 2 elements to determine their

identities– Learn one way to determine the chemical

formula of a material– Compare characteristic properties of a

material to those of its constituent elements

– Represent materials with chemical formulas using numbers and the symbols of elements.

– Practice safe laboratory techniques with flames and explosions

• Do Now:– Read Chapter Challenge

on pg 98-99– Copy LO and SC on new

left side page– WDYS/WDYT-Pg. 101

• You must write at least 2 sentences for each and talk about the SCIENCE!

• Agenda:– Do Now– Investigate– Summary

Do Now:

• Do Now:– Number your notebook pages (1-100 at least)– WDYT-Pg. 101• You must write at least 2 sentences for each and talk

about the SCIENCE!

• Set up notebooks, 1-12– Teacher directed

Do Now

• Open up your notebook, check to make sure that you have it set up for notebook check

• Grab a book and turn to p. 102• Turn to a partner and describe what is going to

happen!

Investigate

• #1 Complete in your notebook, discuss at your table• #2 Complete in your notebook, share at your tables• #3 watch teacher demo of how to set up apparatus• Set up notebooks-teacher led• Assign jobs, complete #4-7

– You must wear safety goggles and aprons at all times!– Do NOT play around, you will lose lab privileges!

• Answer #9

Do Now:

• On p. 101, read through and answer question 1

• Skim through the investigationHW Due Friday: CTG p.109 #1-4

Do Now

• Open up to p. 102– Complete notebook up until number 9 (10

minutes)

Teacher Demo

• #10-12 while running electrolysis

Summary

• Explain how zinc and HCl produced Hydrogen?

• Read through the chem talk—p. 104-107

– When finished, answer the checking up questions in the margin of the last page.

Chem Talk

• What is an element?

• Name 5 elements that you know

• An element is any material that cannot be broken down into simpler materials by chemical means

Chem Talk

• What is Matter? • Anything that is made up of 1 or more elements

• EVERYTHING IS MATTER!

• Different combinations of elements make different things

Chem Talk

• What is Chemistry? • The study of the properties of elements, how the elements combine, the properties of these combinations, and the energy changes that result from these combinations.

Chem Talk

• How do we represent elements?

• We use Symbols to represent elements– O=Oxygen– H=Hydrogen– Cl=Chlorine

• 1st letter is always capitalized• If there is a 2nd letter, it is

lower case– Zn=Zinc– Pb=Lead

• Symbols can be found on the periodic table

Chem Talk

• What is a compound? • When elements combine to form new substances

• Compounds have entirely new characteristics

• Like combining letters to make words

• H2O is a compound – 2 Hydrogens– 1 Oxygen

Chem Talk

• What is electrolysis? • Using electricity in an ionic solution to result in a chemical change

• You did this in the lab when you decomposed water into Hydrogen and Oxygen in the test tubes

• The compound water has very different characteristics from H and O

Chem Talk

• How do we represent Compounds?

• Use a chemical formula– Combination of element

symbols in definite numerical proportions• H2O=2Hydrogens and 1

Oxygen• CCl4=1 Carbon, 4

Chlorines• CO2=?

Chem Talk

• Why do we write chemical equations?

• To “show” what is happening in a chemical reaction

• g=gas, l=liquid, s=solid, aq=aqueous (dissolved in water)

Chem Talk

• Remember Conservation of Mass?

• Matter cannot be created or destroyed…

• What we start with we have to end with!

• We need to apply this to chemical equations

Chem Talk

• More on Conservation of Mass…

• Unbalanced equation…

• Try balancing on your own…

•

Video: Ring of Truth

• http://www.youtube.com/watch?v=buFe-CyQctQ

Proficiency Check:

• Explain the main differences between an element and compound

Proficiency Check

Element or Compound

C CaNaNO3

CO Co

Do Now:

1. Write out the type and how many elements are in the compound.

NaCl H2SO4

C12H22O11 Ba(NO3)2

Summary

2. Go through and prove that you satisfied the Learning Objective

Highlight (underline) areas in your notebook and write a paragraph (2 or 3 sentences) talking about those areas

Worksheet

Do the worksheet on a separate sheet of paper

Summary

Go through and prove that you satisfied the Learning Objective

Highlight areas in your notebook and write a paragraph talking about those areas

When finished:

Essential Questions-pg. 108– What does it mean?– How do you know?– Why should you care?

Chem To Go (CTG)

• Pg. 109, #1-4