BUBBINGTT LESSON 4: EXPLAINING CHEMICAL CHANGE FACTORS OF SCIENTIFIC LITERACY AND FOUNDATIONAL OBJECTIVES, LEARNING OBJECTIVES, SCIENCE 10 BIBLIOGRAPHY
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WHAT HAPPENS TO THE ATOMS AND MOLECULES DURING A CHEMICAL CHANGE?

UNDERSTANDING THE TERMS:

AN ATOM IS THE SMALLEST PARTICLE OF AN ELEMENT.

AN ELEMENT IS A BUILDING BLOCK OF MATTER. ALL THE ELEMENTS ARE FOUND ON THE PERIODIC TABLE.

A MOLECULE IS FORMED WHEN TWO OR MORE ATOMS COMBINE. IF THE ATOMS ARE THE SAME THE MOLECULE IS THAT OF AN ELEMENT. IF THE ATOMS ARE DIFFERENT THEN THE MOLECULE IS THAT OF A COMPOUND.

A COMPOUND IS FORMED FROM THE COMBINING OF TWO OR MORE ELEMENTS.

WHEN TWO ATOMS ARE COMBINED WITHIN A MOLECULE AN ATTRACTIVE FORCE KNOWN AS A CHEMICAL BOND IS KEEPING THE ATOMS TOGETHER.

REACTANTS ARE THE STARTING MATERIALS OF A CHEMICAL REACTION.

PRODUCTS ARE THE MATERIALS MADE AS A RESULT OF THE CHEMICAL REACTION.

THE CHEMICAL REACTION IS THE PROCESS BY WHICH THE REACTANTS CHANGE AND TURN INTO PRODUCTS. YOU USUALLY SEE THINGS LIKE A PRECIPITATE FORM, A GAS FORM, A COLOR CHANGE OR A CHANGE OF TEMPERATURE WHEN A CHEMICAL REACTION OCCURS.

WE MUST DEVELOP A MENTAL PICTURE OR MODEL FOR THE PROCESS OF A CHEMICAL REACTION.

OVER TIME SCIENTISTS HAVE DEVELOPED THEIR IDEAS ABOUT HOW THE TINY PARTICLES OF THE REACTANTS MUST BEHAVE IN ORDER TO ACCOMPLISH THE CHANGES NECESSARY TO MAKE AN ENTIRELY NEW SUBSTANCE. THE PARTICLES MAKING UP THE REACTANTS HAVE TO TOTALLY REARRANGE THEMSELVES. THEY DO THIS BY:

  • THE BONDS WITHIN THE REACTANTS ARE BROKEN
  • THE RESULTING ATOMS FORM NEW BONDS AND THEREBY MAKE SOMETHING ENTIRELY DIFFERENT, KNOWN AS THE PRODUCT(S)

IT IS OFTEN SAID THAT DURING A CHEMICAL REACTION, OLD BONDS IN THE REACTANTS BREAK AND NEW BONDS FORM MAKING THE PRODUCT(S).

IN THIS LESSON YOU WILL LOOK AT A FEW MODELS THAT PEOPLE HAVE USED TO EXPLAIN HOW A CHEMICAL CHANGE OCCURS. THEN YOU WILL DEVELOP YOUR OWN MENTAL PICTURE OR MODEL THAT YOU CAN USE TO ILLUSTRATE CHEMICAL CHANGE.

ACTIVITY

READ A VARIETY OF RESOURCES ON CHEMICAL CHANGE AND THE MODELS THEY TALK ABOUT. WHILE YOU READ, TRY TO IMAGINE WHAT IS HAPPENING TO THE ATOMS AND MOLECULES DURING A CHEMICAL REACTION.

1. READ PAGE 174 AND 175 OF THE DISCOVERING PHYSICAL SCIENCE TEXTBOOK.
2.

READ ABOUT DALTONS ATOMIC THEORY:

  • ON PAGES 190 AND 191 OF THE DISCOVERING PHYSICAL SCIENCE TEXTBOOK
  • ON PAGES 71 AND 72 OF THE CHEMICALS IN ACTION TEXTBOOK
3. READ ABOUT ATOMS AND MOLECULES ON PAGES 179 TO 182 OF THE PHYSICAL SCIENCE AN INTRODUCTORY STUDY TEXTBOOK.
4.

READ SITES ON THE NET. REMEMBER TO SCROLL DOWN AND READ. YOU ARE LOOKING FOR SECTIONS THAT TELL YOU ABOUT DALTON'S ATOMIC THEORY, THE MODERN ATOMIC THEORY, ATOMS, MOLECULES AND CHEMICAL CHANGE.

5. SEARCH THE INTERNET TO LEARN STILL MORE ON ATOMS, MOLECULES, ELEMENTS, COMPOUNDS, CHEMICAL CHANGE, CHEMICAL REACTIONS, DALTON'S ATOMIC THEORY AND THE MODERN ATOMIC THEORY.

ASSIGNMENT

DRAW A REPRESENTATION (A PICTURE) OF HOW YOU THINK A CHEMICAL REACTION WORKS. USE THE REACTION BETWEEN HYDROGEN AND CHLORINE AS AN EXAMPLE.

WORD EQUATION: HYDROGEN (G) + CHLORINE (G) ARROW HYDROGEN CHLORIDE (G)
CHEMICAL EQUATION: HCL BALANCED CHEMICAL EQUATION

THIS PICTURE SHOULD SHOW HOW YOU THINK THE PARTICLES ARE ARRANGED AS REACTANTS AND HOW THIS ARRANGEMENT CHANGES IN ORDER TO MAKE THE ENTIRELY NEW SUBSTANCE KNOWN AS THE PRODUCT.

COMPARE YOUR PICTURE WITH THE PICTURE OF THREE OF YOUR CLASSMATES. TRY TO AGREE ON THE BEST PICTURE AMONG THE FOUR OF YOU. THE BEST PICTURE WOULD BE IN KEEPING WITH DALTON'S ATOMIC THEORY. THE BEST PICTURE WOULD:

  • SHOW THE ORIGINAL REACTANT PARTICLES OF BOTH REACTANTS
  • SHOW THE PRODUCT PARTICLES
  • SHOW HOW THE PRODUCT HAS DIFFERENT PROPERTIES THAN THE REACTANTS
  • SHOW HOW ONE ELEMENT COULD BE RECOVERED FROM ITS COMPOUND IF WE CHOSE FOR THAT TO HAPPEN.
  • SHOW THAT MASS IS CONSERVED IN THE CHEMICAL REACTION

WRITE YOUR NAME IN THE UPPER RIGHT HAND CORNER OF YOUR PICTURE.

AT THE BOTTOM OF YOUR PICTURE, WRITE A SENTENCE SIMILAR TO THIS ONE. "I COMPARED MY PICTURE TO: NAME 1, NAME 2 AND NAME 3. SO AND SO HAD THE BEST PICTURE OF HOW THE REACTION BETWEEN HYDROGEN AND CHLORINE HAPPENS."

POST EACH PERSONS PICTURE ON THE BULLETIN BOARD. THE PEOPLE IN YOUR GROUP OF FOUR SHOULD POST THEIR PICTURES SIDE BY SIDE HAVING THE "BEST" PICTURE PLACED ON THE EXTREME LEFT WITHIN THE GROUP. IN A REGULAR CLASSROOM, THE CLASS AS A WHOLE MAY DISCUSS THE DIFFERENT PICTURES FROM THE VARIOUS GROUPS. ONLINE STUDENTS MAY POST THEIR WORK ON THE SITE INDICATED BY YOUR ONLINE TEACHER. AN ONLINE DISCUSSION OF THE PICTURES MAY THEN TAKE PLACE. YOUR TEACHER WILL GRADE YOUR WORK.

ASSESSMENT

YOUR PICTURE OR MODEL OF HOW A CHEMICAL REACTION OCCURS REFLECTS YOUR UNDERSTANDING OF CHEMICAL REACTIONS.

YOUR WORK WILL BE SCORED OUT OF 10 MARKS. GRADING WILL BE BASED ON:

  • DID YOU PICK THE BEST PICTURE OF YOUR GROUP?
  • DID YOU PERSONALLY HAVE AN ADEQUATE VISION OF HOW A CHEMICAL REACTION OCCURS?
  • DID YOU YOURSELF SHOW THAT YOU UNDERSTAND HOW THE PARTICLES EXIST AS REACTANTS AND HOW THEY ARE REARRANGED TO MAKE SOMETHING NEW DURING A CHEMICAL REACTION?
  • DID YOU LABEL YOUR PICTURE IN SUCH A WAY THAT OTHERS CAN ACCURATELY INTERPRET YOUR PICTURE?