English Language Development

Snapshot 6.5. Making Inferences Using a Graphic Organizer

Integrated ELA/Literacy and Science Lesson in Grade Seven (cont.)

“That’s right. It’s used to show the presence of a chemical or a change in that chemical.

Bromothymol blue indicates the presence of an acid or a base. I think I remember reading

this in the article we read yesterday.” On the document reader, Mr. Schoen shows the students

where in the text this information can be found. “Now let’s add a piece of dry ice to our beaker

and solution.”

Using tongs he picks up one of several small chunks of dry ice in a bowl and moves to

drop it in the solution. Just before placing it in the solution, Mr. Schoen pauses and asks

“What do you think will happen? You have thirty seconds to tell your partner.” Amid groans

of anticipation, he then listens to several responses as he calls on students to share out: “the

color will change, there will be no color change, it will make bubbles, nothing will happen” and

so on. After thanking them for their responses, Mr. Schoen drops the piece of dry ice into the

solution. It immediately begins to bubble as the dry ice sublimates. The bromothymol blue

solution turns yellow. After a few moments Mr. Schoen adds some drops of sodium hydroxide,

just enough to cause the color to change back to blue.

Mr. Shoen then thinks aloud, “I know that I need to think like a scientist and try to figure

out what is happening. I wonder why the color of the water changed? Well, I know from the

reading that a color change indicates a chemical reaction.” He shows the students where

this information is in the text and invites the students to highlight the relevant text before

continuing.

“I think something about the dry ice reacted with the water and the sodium hydroxide

reversed that reaction. Because I already know from previous lessons we’ve done that water

is usually neutral, I can infer that the color changes are related to turning the water acidic or

neutralizing it with a base. The sodium hydroxide returned the water solution to its original

color, so it must be a base. I’m going to record this on my graphic organizer.”

The Demonstration

Showed

I Know

(from texts and

background knowledge)

Inference

(conclusion drawn from

evidence and reasoning)

• Solution bubbled and
  changed from blue to
  yellow when dry ice
  was added.


• It changed back to blue
  when sodium hydroxide
  was added.
  
  
  • Color changes indicate
    chemical reactions.
  
  
  • Water usually has a
    neutral pH.
  
  
  • The yellow color means
    it is an acidic solution.
    
    
    • Adding dry ice to the
      water resulted in the
      water turning acidic.
    
    
    
    
  
  
  
  

After this modeling, Mr. Schoen describes the next task by saying, “Now it is your turn to

make inferences with your partner. I’d like you to make five inferences using three sources:

information on acids and bases from the article we’ve already read, your partner’s and your

background knowledge, and the demonstration you just observed. Remember to consider

what we have read, as well as other labs and activities we have done. I’d also like for you to

use science words, such as ‘solution’ or ‘chemical reaction,’ as well as some of the phrases I

586 | Chapter 6 Grade 7