Counting Atoms and Balancing Chemical Equations Write what is in Blue - PowerPoint PPT Presentation

Loading...

PPT – Counting Atoms and Balancing Chemical Equations Write what is in Blue PowerPoint presentation | free to download - id: 4208ed-YTZlY



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Counting Atoms and Balancing Chemical Equations Write what is in Blue

Description:

Counting Atoms and Balancing Chemical Equations Write what is in Blue Elements, Compounds, Mixtures Hydrogen is an element. Oxygen is an element. – PowerPoint PPT presentation

Number of Views:186
Avg rating:3.0/5.0
Slides: 32
Provided by: tech182
Learn more at: http://www.gcisd-k12.org
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Counting Atoms and Balancing Chemical Equations Write what is in Blue


1
Counting Atoms and Balancing Chemical
Equations Write what is in Blue
2
Elements, Compounds, Mixtures
  • Hydrogen is an element.
  • Oxygen is an element.
  • When hydrogen and oxygen bond they make the
    compound water.
  • When salt and water are combined, a mixture is
    created. Compounds in mixtures retain their
    individual properties.

The ocean is a mixture.
3
Elements, compounds, and mixtures
  • Mixtures can be separated by physical means.
  • Compounds can only be separated by chemical
    means.
  • Elements are pure substances. When the subatomic
    particles of an element are separated from its
    atom, it no longer retains the properties of that
    element.

4
Identifying Compounds
  • Each new element is identified by a capital
    letter
  • Example H2SO4
  • The elements in Sulfuric Acid
  • Hydrogen
  • Sulfur
  • Oxygen

5
Subscripts
  • C12H22O11
  • There are 12 atoms of Carbon
  • There are 22 atoms of Hydrogen
  • There are 11 atoms of Oxygen
  • If there is not a subscript listed, it is
    understood to be 1.
  • Example NaCl
  • There is one atom of Sodium
  • There is one atom of Chlorine

6
You Practice!
  • NaHCO3
  • Sodium 1
  • Hydrogen 1
  • Carbon 1
  • Oxygen -3
  • HCl
  • Hydrogen 1
  • Chlorine - 1

7
  • There are times you will see a compound with
    parenthesis.
  • Pb(NO3)2
  • The 2 after the parenthesis indicates there are
    two sets of the parenthesis.
  • Pb(NO3) (NO3)
  • So, in counting the atoms, you would have the
    following
  • Lead 1 Oxygen - 6
  • Nitrogen -2

8
You Practice!!
  • (NH4)3PO4
  • Nitrogen 3
  • Hydrogen 12
  • Phosphorus 1
  • Oxygen 4
  • Mg(OH)2
  • Magnesium 1
  • Oxygen 2
  • Hydrogen 2

9
Coefficient
  • 2H2SO4
  • This means there are 2 compounds of Sulfuric
    Acid. Think
  • H2SO4 H2SO4
  • Counting the atoms
  • Hydrogen 4
  • Sulfur 2
  • Oxygen - 8

10
You Practice!!
  • 3H3PO4
  • Hydrogen 9
  • Phosphorus 3
  • Oxygen - 12
  • 2H2O
  • Hydrogen 4
  • Oxygen - 2

11
Got It????
12
Movin' On!!
13
Chemical Equations
  • Chemical equations express what is happening in a
    chemical reaction using symbols.
  • 4K Cl2 2KCl
  • Reactant Product

14
Law of Conservation of Mass
  • In a chemical reaction, matter cannot be created
    or destroyed. It can only be changed.

15
What does that mean??
  • The reactants MUST contain the same elements and
    the same number of each element as the product.
    They CAN be in different compounds.

16
HUH?????
  • H2 O2 H2O
  • Reactants H 2 O 2
  • Products H 2 O 1
  • This cannot happen. An oxygen atom cannot be
    destroyed.

17
So what do we do?
  • The chemical equation must be written according
    to the law.
  • AGAIN --- HUH???
  • H2 O2 H2O is the production of water.
    Well, how it actually happens in nature is this.
  • 2H2 O2 2H2O
  • Reactants H 4 O 2
  • Products H 4 O 2

18
Do I Need to Know How to Balance?
  • NOT YET. You need to be able to recognize if the
    chemical reaction follows the law of conservation
    of mass.
  • Na O2 Na2O
  • Mg 2HCl MgCl2 H2

NOPE
YUP!!
19
You Practice!!!
  • HgO Hg O2
  • N2 3H2 2NH3
  • Zn 2HCl ZnCl2 H2

NOPE
YUP
YUP
20
More Practice
  • K Br2 2KBr
  • 2Fe O2 6Fe2O3
  • 2Na 2H2O 2NaOH H2

NOPE
NOPE
YUP
21
Got It???
22
Warm Up 3/9 Is it balanced? Show your work!!
  • Al O2 ---gt Al2O3
  • SiCl4 H2O ---gt H4SiO4 HCl

23
Balancing Chemical Equations
  • H2 O2 H2O
  • Reactants H 2 Products H 2
  • O 2 O 1
  • What do we multiply by 1 to get 2?

24
Keep Going.
  • H2 O2 2H2O
  • Reactants Products
  • 2H 4
  • 2 O 2
  • Now the Oxygen is balanced but Hydrogen is not,
    so what do we multiply by 2 to get 4?

25
Almost There!!!
  • 2H2 O2 2H2O
  • Reactants Products
  • 4 H 4
  • 2O 2
  • Now it is balanced!!! Congratulations, you have
    now learned the hardest thing we will do all
    year!!

26
Now You Practice
  • HgO Hg O2
  • Hg
  • O
  • K Br2 2KBr
  • K
  • Br

27
Warm Up 3/11 Write QA
  • Why do we have to balance equations? (What law do
    we have to follow?)

28
Warm Up 3/10 Write QA
  • Balance the Following
  • HNO3 Ca(OH)2 ? Ca(NO3)2 H2O

29
Warm Up 3/8 Write the Following
  • The Law of Conservation of Mass
  • In a chemical reaction, matter cannot be created
    or destroyed. It can only be changed.

30
Warm Up 3/5 Write QA
  • How many atoms are in 3Pb(OH)4?
  • Pb
  • O
  • H

31
Warm Up March 4 Write QA
  • The vertical columns on the periodic table are
    called ______________ and they correspond to the
    number of __________
  • The horizontal rows on the periodic table are
    called ____________ and they correspond to the
    number of __________
About PowerShow.com