Overview

Lesson Procedure

65-75 minutes of class time across 5 phases.

1. Warm-Up10 minutes
2. Direct Instruction20 minutes
3. Guided Practice15 minutes
4. Independent Practice15-20 minutes
5. Closure5-10 minutes

1. Warm-Up10 minutes

   Project two lab notes about the same test and ask students which one lets a reader explain what happened.

   Warm-Up Prompt

   "Note A: The ice melted faster on the metal. Note B: Two 20 g ice cubes were placed at the same time on an aluminum block and on a plastic block of the same size, both at room temperature. The cube on the aluminum was completely melted after 2 minutes 40 seconds; the cube on the plastic still had a solid core after 10 minutes. Which note would you cite to prove that the aluminum carried heat to the ice faster? Underline the three details you would quote."

   The data in Note B are invented for this warm-up. Collect answers and list the details students underlined: the equal starting mass (20 g), the same starting time and temperature, the exact times. Point out that Note A makes the same claim but gives nothing to cite. Tell students that RST.9-10.1 asks for exactly this: evidence from the text, and attention to the precise details that make an explanation or description checkable.

2. Direct Instruction20 minutes

   Part 1: Explanations, descriptions and precise details. An explanation tells how or why something happens; a description tells what something is like, where it is or how it is arranged. In both, the evidence is usually a small detail: a cause word such as "because" or "so," a condition such as "if," a location, a number or an exception. Use the table to name the kinds of detail students will look for.

   Precise details to look for in science and technical texts

   Kind of detail	Signal words	What it tells the reader
   Cause and effect	because, so, therefore, by the force of	Why something happens: the explanation itself
   Condition	if, when, provided, unless	When the explanation holds and when it fails
   Location	in the middle, on the outside, at the edge	Where in the object or apparatus something happens
   Quantity and measure	numbers, units, at least, to the nearest	How much, how long, how far
   Sequence	first, then, as soon as, after	The order a process or procedure follows
   Exception	except, only, not	The case the general statement does not cover
   Definition or distinction	is, means, the difference between	How the author uses a key term

   Part 2: Model with Faraday. Explain the setting: Faraday gave these lectures to a young audience, demonstrating each point with a real candle. Read the excerpt aloud. Then work through the examples, asking after each: which words would you quote, and what kind of detail are they? Use Diagram 1 to locate each detail on a flame, and Diagram 2 with example 4.

   You see, then, in the first instance, that a beautiful cup is formed. As the air comes to the candle it moves upwards by the force of the current which the heat of the candle produces, and it so cools all the sides of the wax, tallow, or fuel, as to keep the edge much cooler than the part within; the part within melts by the flame that runs down the wick as far as it can go before it is extinguished, but the part on the outside does not melt. If I made a current in one direction, my cup would be lop-sided, and the fluid would consequently run over,—for the same force of gravity which holds worlds together holds this fluid in a horizontal position, and if the cup be not horizontal, of course the fluid will run away in guttering. You see, therefore, that the cup is formed by this beautifully regular ascending current of air playing upon all sides, which keeps the exterior of the candle cool. No fuel would serve for a candle which has not the property of giving this cup, except such fuel as the Irish bogwood, where the material itself is like a sponge, and holds its own fuel. You see now why you would have had such a bad result if you were to burn these beautiful candles that I have shewn you, which are irregular, intermittent in their shape, and cannot therefore have that nicely-formed edge to the cup which is the great beauty in a candle. I hope you will now see that the perfection of a process—that is, its utility—is the better point of beauty about it. It is not the best looking thing, but the best acting thing, which is the most advantageous to us.

   • Explanation: cause and effect

     Why does a burning candle form a cup that holds its melted fuel?

     Result: Faraday gives a chain of causes: the heat of the candle produces an upward current of air, and that air "so cools all the sides of the wax, tallow, or fuel, as to keep the edge much cooler than the part within." The inside melts; "the part on the outside does not melt." The cited words are the cause (the rising air), the effect (a cool edge) and the result (a solid rim around the melt).

   • Condition: when the explanation fails

     What does Faraday say would happen if the air did not rise evenly?

     Result: "If I made a current in one direction, my cup would be lop-sided, and the fluid would consequently run over." The precise detail is the condition "in one direction": the cup depends on a "beautifully regular ascending current of air playing upon all sides." A student who writes only "wind ruins candles" has missed the condition.

   • Exception

     Does Faraday claim that every fuel must form a cup?

     Result: Almost: "No fuel would serve for a candle which has not the property of giving this cup, except such fuel as the Irish bogwood, where the material itself is like a sponge, and holds its own fuel." An accurate summary keeps the exception and the reason for it (the bogwood holds its own fuel).

   • From vague to precise evidence

     Claim: Faraday cares more about how a candle works than how it looks. Which evidence supports it best?

     Result: Weak: "Faraday talks about beautiful candles." Strong: he says the candles that are "irregular, intermittent in their shape" cannot have "that nicely-formed edge to the cup," and concludes, "It is not the best looking thing, but the best acting thing, which is the most advantageous to us." The strong version quotes the reason and the conclusion (Diagram 2 shows the same climb for a different claim).

3. Guided Practice15 minutes

   Pairs read the second Faraday excerpt, from later in the same lecture. They highlight explanation in one color and description in the other, then complete a three-column chart: question, precise detail quoted, what it explains. Give the questions: What must the vapour be kept from doing? How does Faraday show that the vapour, not the wick, carries the fire back to the candle? Circulate and push for precision: "he lights it" is a start; "he holds 'a lighted taper two or three inches from the wick' and sees 'a train of fire going through the air till it reaches the candle'" is evidence.

   There is another condition which you must learn as regards the candle, without which you would not be able fully to understand the philosophy of it, and that is the vaporous condition of the fuel. In order that you may understand that, let me shew you a very pretty, but very common-place experiment. If you blow a candle out cleverly, you will see the vapour rise from it. You have, I know, often smelt the vapour of a blown-out candle—and a very bad smell it is; but if you blow it out cleverly, you will be able to see pretty well the vapour into which this solid matter is transformed. I will blow out one of these candles in such a way as not to disturb the air around it, by the continuing action of my breath; and now, if I hold a lighted taper two or three inches from the wick, you will observe a train of fire going through the air till it reaches the candle. I am obliged to be quick and ready, because, if I allow the vapour time to cool, it becomes condensed into a liquid or solid, or the stream of combustible matter gets disturbed.

   Debrief with one question: Why does Faraday say he is "obliged to be quick and ready"? Students should cite both reasons he gives (the vapour "becomes condensed into a liquid or solid," or "the stream of combustible matter gets disturbed") and notice the word "or": either one ends the demonstration.

   For Activity 2 (Procedure Precision Check). The procedure below was written for this page. It is a safe test with water and no flame.

   Purpose: to compare how high colored water rises by capillary action in three wick materials during 10 minutes.

   Materials: one strip each of cotton cloth, white paper towel and nylon ribbon, each 1 cm wide and 12 cm long; a 250 mL glass beaker holding 150 mL of tap water tinted with 3 drops of blue food coloring; a pencil; tape; a metric ruler; a timer.

   1. With the pencil, draw a line across each strip 2 cm from one end. Use pencil, not ink: ink can run when it gets wet and blur the line.

   2. Tape the other end of each strip to the pencil so that the strips hang 2 cm apart. Wind the tops around the pencil until each pencil line will sit exactly at the water surface.

   3. Rest the pencil across the rim of the beaker. Check that no strip touches another strip or the glass. A strip that touches the glass can draw water along the wall, so its reading does not count.

   4. Start the timer the moment the strips touch the water. At 1, 5 and 10 minutes, measure the height of the blue front above the pencil line to the nearest millimeter. If the front is uneven, record its highest point and write "uneven" beside the reading.

   5. Repeat the test twice more with fresh, dry strips. Report the mean of the three trials for each material and time.

4. Independent Practice15-20 minutes

   Students read Faraday's account from Lecture II of what he finds inside the flame and answer quiz questions 1-20 on their own with the passage open. Paragraph numbers are printed beside the text. The "[...]" marks a part of the lecture left out here, in which Faraday repeats his test on a larger scale. The "diagram" and "fig. 7" he mentions are drawings in the book that this page does not reproduce; Diagram 1 is a simple modern sketch.

   1Here is a candle: I am about to put the end of this glass tube into the middle of the flame—into that part which old Hooke has represented in the diagram as being rather dark, and which you can see at any time, if you will look at a candle carefully, without blowing it about. We will examine this dark part first.

   2Now, I take this bent glass tube, and introduce one end into that part of the flame, and you see at once that something is coming from the flame, out at the other end of the tube; and if I put a flask there, and leave it for a little while, you will see that something from the middle part of the flame is gradually drawn out, and goes through the tube and into that flask, and there behaves very differently from what it does in the open air. It not only escapes from the end of the tube, but falls down to the bottom of the flask like a heavy substance, as indeed it is. We find that this is the wax of the candle made into a vaporous fluid—not a gas. (You must learn the difference between a gas and a vapour: a gas remains permanent, a vapour is something that will condense.)

   [...]

   3I shall get no vapour from that part which is already burnt. If I raise the tube (fig. 7) to the upper part of the flame, so soon as the vapour has been swept out, what comes away will be no longer combustible: It is already burned. How burned? Why, burned thus:—In the middle of the flame, where the wick is, there is this combustible vapour; on the outside of the flame is the air which we shall find necessary for the burning of the candle; between the two, intense chemical action takes place, whereby the air and the fuel act upon each other, and at the very same time that we obtain light the vapour inside is destroyed. If you examine where the heat of a candle is, you will find it very curiously arranged. Suppose I take this candle, and hold a piece of paper close upon the flame, where is the heat of that flame? Do you not see that it is not in the inside? It is in a ring, exactly in the place where I told you the chemical action was; and even in my irregular mode of making the experiment, if there is not too much disturbance, there will always be a ring. This is a good experiment for you to make at home. Take a strip of paper, have the air in the room quiet, and put the piece of paper right across the middle of the flame (I must not talk while I make the experiment), and you will find that it is burnt in two places, and that it is not burnt, or very little so, in the middle; and when you have tried the experiment once or twice, so as to make it nicely, you will be very interested to see where the heat is, and to find that it is where the air and the fuel come together.

5. Closure5-10 minutes

   Exit ticket: "Write one claim about the candle that you can support from the passages. Then quote the one precise detail that best supports it, and name the kind of detail (cause, condition, location, quantity, sequence, exception or definition)." Sort the tickets into "quotes the topic" and "quotes the detail" to plan the next lesson.

   Teacher note on the 1861 text. Faraday's spelling is British and of its time ("shew" for show, "vapour"), and the quotations keep it exactly. His science also needs two notes. The distinction between a gas and a vapour at the end of paragraph 2 of the quiz passage was common in 1861; today chemists call a vapor the gas form of a substance that is normally a liquid or solid at room temperature, and any gas turns liquid if it is cooled enough. Discuss this after the quiz. Second, Faraday calls the paper experiment "a good experiment for you to make at home." Do not assign it: an open flame and paper belong in a teacher demonstration with fire safety in place, or on video.

   Homework passage. The homework uses the page of an instrument manual below, written for this page and modeled on the notes that come with a school electronic balance. Tell students that manuals are technical texts too: every detail is there because leaving it out can spoil a measurement.

   1Capacity: 200 g. Readability: 0.01 g. Use between 15 and 30 °C.

   2Placement. Set the balance on a firm, level table away from doors, air vents and sunny windows. Turn the two leveling feet until the bubble sits inside the circle of the level indicator. A balance that is not level can give readings that look steady but are slightly wrong.

   3Warm-up. Switch the balance on at least 15 minutes before use. Readings taken sooner may drift while the electronics warm up.

   4Weighing. Place the empty container at the center of the pan, close the draft shield and press TARE. The display returns to 0.00 g. Add the sample and wait for the stability symbol (a small circle at the left of the display) before you record the reading. The tared container still counts toward the 200 g capacity. If the total load is over capacity, the display shows -OL- and no reading is given.

   5Warm or cold samples. Let every sample reach room temperature before weighing. A warm object heats the air around it, and the rising air makes the reading lower than the true mass and unsteady. A cold object does the opposite.

   6Calibration. Calibrate the balance after it is moved to a new place and at least once a month. With the pan empty and the display at 0.00 g, hold CAL for 3 seconds until 100 flashes. Place the 100 g calibration mass at the center of the pan with the tweezers provided, and remove it when the display reads End. Use only the calibration mass supplied with the balance.

Differentiation Strategies

Assessment Guidance

1. Question 1 of 20 · Multiple Choice

   According to paragraph 1, where does Faraday put the end of the glass tube?

   AInto the bright top of the flame BInto the dark middle part of the flame CInto the melted wax in the cup DInto the air just beside the flame

2. Question 2 of 20 · Multiple Choice

   What does the substance drawn through the tube do when it reaches the flask?

   AIt rises out of the flask like smoke BIt catches fire by itself CIt falls to the bottom of the flask like a heavy substance DIt turns into water on the glass

3. Question 3 of 20 · Multiple Choice

   What does Faraday say the substance in the flask is?

   AA gas made from the air around the flame BSoot from the wick CWater given off by the flame DThe wax of the candle made into a vapour

4. Question 4 of 20 · Multiple Choice

   Which detail in paragraph 2 tells how long the flask must stay at the end of the tube before the substance collects?

   A"leave it for a little while" B"you see at once" C"as indeed it is" D"so soon as the vapour has been swept out"

5. Question 5 of 20 · Multiple Choice

   What comes out of the tube when Faraday raises it to the upper part of the flame, once the vapour has been swept out?

   AMore wax vapour than before BSomething that is no longer combustible, because it is already burned CMelted wax that drips back down DFresh air from outside the flame

6. Question 6 of 20 · Multiple Choice

   According to paragraph 3, where does the "intense chemical action" take place?

   ABetween the combustible vapour in the middle and the air on the outside BInside the wick CIn the flask DBelow the flame, in the melted fuel

7. Question 7 of 20 · Multiple Choice

   Which phrase tells when the vapour inside the flame is destroyed?

   A"If I raise the tube (fig. 7) to the upper part of the flame" B"if there is not too much disturbance" C"at the very same time that we obtain light" D"when you have tried the experiment once or twice"

8. Question 8 of 20 · Multiple Choice

   Where does Faraday say the heat of the flame is?

   AEvenly spread through the whole flame BIn the middle, around the wick COnly at the very tip of the flame DIn a ring, where the chemical action is

9. Question 9 of 20 · Multiple Choice

   In the paper experiment, how is the strip of paper burnt?

   AIn one spot in the middle BIn two places, and little or not at all in the middle CEvenly across its whole width DOnly at its edges, where the student holds it

10. Question 10 of 20 · Multiple Choice

    Faraday writes that the paper "is not burnt, or very little so, in the middle." What do the words "or very little so" add?

    AThey make the description exact: the middle may be slightly scorched, not always untouched BThey show that Faraday is unsure whether the paper burns at all CThey mean the middle burns more than the edges DThey tell the reader to use very little paper

11. Question 11 of 20 · Multiple Choice

    In paragraph 3, what does "this" refer to in "there is this combustible vapour"?

    AThe smoke of a blown-out candle BThe air on the outside of the flame CThe wax vapour drawn from the dark middle in paragraph 2 DThe burned matter from the top of the flame

12. Question 12 of 20 · Multiple Choice

    Whose drawing does Faraday rely on in paragraph 1 to point out the dark part of the flame?

    AHis own sketch on the board BA photograph of a flame CA drawing by his assistant DA diagram by Hooke

13. Question 13 of 20 · Multiple Choice

    What is the purpose of the sentence in parentheses at the end of paragraph 2?

    ATo give the source of Faraday's experiment BTo define a distinction the reader needs in order to understand the words "not a gas" CTo warn the audience about the smell of the vapour DTo describe how to build the glass tube

14. Question 14 of 20 · Multiple Choice

    The substance "falls down to the bottom of the flask like a heavy substance, as indeed it is." What do the words "as indeed it is" tell the reader?

    AThat the vapour really is heavier than the air, not only in appearance BThat the vapour is heavier than the melted wax CThat Faraday weighed the vapour on a scale DThat the vapour is only imitating a heavy substance

15. Question 15 of 20 · Short Answer

    Trace the path of the substance from the flame to the flask. Cite at least two precise details from paragraph 2.

    Show model answer

16. Question 16 of 20 · Short Answer

    Faraday calls the substance in the flask "a vaporous fluid" and says it is "not a gas." Using his own definition in paragraph 2, predict what would happen to the substance if the flask were set aside to cool, and quote the words that support your prediction.

    Show model answer

17. Question 17 of 20 · Short Answer

    Faraday asks, "How burned?" In your own words, explain his answer, citing the three parts of the flame he names in paragraph 3.

    Show model answer

18. Question 18 of 20 · Short Answer

    A classmate writes: "Faraday shows that you can collect wax vapour from any part of the flame." Correct the claim with precise details from paragraphs 1-3.

    Show model answer

19. Question 19 of 20 · Short Answer

    Paragraph 3 moves from an explanation of how the flame burns to a description of an experiment with paper. Explain how the result of the experiment supports the explanation. Cite one detail from each.

    Show model answer

20. Question 20 of 20 · Short Answer

    Faraday gives conditions for the paper experiment to show its result clearly. Quote two of them, and explain why each matters, using what paragraph 3 says about where the heat is.

    Show model answer

These standards connect to RST.9-10.1: prerequisites to review first, parallel standards at the same level, and next steps that build on it.

Standard text: Common Core State Standards for English Language Arts & Literacy. © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.