Daughters of Invention

Julia Alvarez

That Sunday evening, I was reading some poetry to get myself inspired: Whitman in an old book with an engraved cover my father had picked up in a thrift shop next to his office a few weeks back. “I celebrate myself and sing myself. . .” “He most honors my style who learns under it to destroy the teacher.” The poet’s words shocked and thrilled me. I had gotten used to the nuns, a literature of appropriate sentiments, poems with a message, expurgated texts. But here was a flesh and blood man, belching and laughing and sweating in poems. “Who touches this book touches a man.”

That night, at last, I started to write, recklessly, three, five pages, looking up once only to see my father passing by the hall on tiptoe. When I was done, I read over my words, and my eyes filled. I finally sounded like myself in English!

As soon as I had finished that first draft, I called my mother to my room. She listened attentively, as she had to my father’s speech, and in the end, her eyes were glistening too. Her face was soft and warm and proud. “That is a beautiful, beautiful speech, Cukita. I want for your father to hear it before he goes to sleep. Then I will type it for you, all right?”

Down the hall we went, the two of us, faces flushed with accomplishment. Into the master bedroom where my father was propped up on his pillows, still awake, reading the Dominican papers, already days old. He had become interested in his country’s fate again. The dictatorship had been toppled. The interim government was going to hold the first free elections in thirty years. There was still some question in his mind whether or not we might want to move back. History was in the making, freedom and hope were in the air again! But my mother had gotten used to the life here. She did not want to go back to the old country where she was only a wife and a mother (and a failed one at that, since she had never had the required son). She did not come straight out and disagree with my father’s plans. Instead, she fussed with him about reading the papers in bed, soiling those sheets with those poorly printed, foreign tabloids. “The Times is not that bad!” she’d claim if my father tried to humor her by saying they shared the same dirty habit.

The minute my father saw my mother and me, filing in, he put his paper down, and his face brightened as if at long last his wife had delivered a son, and that was the news we were bringing him. His teeth were already grinning from the glass of water next to his bedside lamp, so he lisped when he said, “Eh-speech, eh-speech!”

“It is so beautiful, Papi,” my mother previewed him, turning the sound off on his TV. She sat down at the foot of the bed. I stood before both of them, blocking their view of the soldiers in helicopters landing amid silenced gun reports and explosions. A few weeks ago it had been the shores of the Dominican Republic. Now it was the jungles of Southeast Asia they were saving. My mother gave me the nod to begin reading.

I didn’t need much encouragement. I put my nose to the fire, as my mother would have said, and read from start to finish without looking up. When I was done, I was a little embarrassed at my pride in my own words. I pretended to quibble with a phrase or two I was sure I’d be talked out of changing. I looked questioningly to my mother. Her face was radiant. She turned to share her pride with my father.

But the expression on his face shocked us both. His toothless mouth had collapsed into a dark zero. His eyes glared at me, then shifted to my mother, accusingly. In barely audible Spanish, as if secret microphones or informers were all about, he whispered, “You will permit her to read that?”

My mother’s eyebrows shot up, her mouth fell open. In the old country, any whisper of a challenge to authority could bring the secret police in their black V.W.’s. But this was America. People could say what they thought. “What is wrong with her speech?” my mother questioned him.

What ees wrrrong with her eh-speech?” My father wagged his head at her. His anger was always more frightening in his broken English. As if he had mutilated the language in his fury—and now there was nothing to stand between us and his raw, dumb anger. “What is wrong? I will tell you what is wrong. It shows no gratitude. It is boastful. ‘I celebrate myself’? ‘The best student learns to destroy the teacher’?” He mocked my plagiarized words. “That is

insubordinate. It is improper. It is disrespecting of her teachers—” In his anger he had forgotten his fear of lurking spies: Each wrong he voiced was a decibel higher than the last outrage. Finally, he was yelling at me, “As your father, I forbid you to say that eh-speech!”

My mother leapt to her feet, a sign always that she was about to make a speech or deliver an ultimatum. She was a small woman, and she spoke all her pronouncements standing up, either for more protection or as a carry-over from her girlhood in convent schools where one asked for, and literally took, the floor in order to speak. She stood by my side, shoulder to shoulder; we looked down at my father. “That is no tone of voice, Eduardo—” she began. By now, my father was truly furious. I suppose it was bad enough I was rebelling, but here was my mother joining forces with me. Soon he would be surrounded by a house full of independent American women. He too leapt from his bed, throwing off his covers. The Spanish newspapers flew across the room. He snatched my speech out of my hands, held it before my panicked eyes, a vengeful, mad look in his own, and then once, twice, three, four, countless times, he tore my prize into shreds.

“Are you crazy?” My mother lunged at him. “Have you gone mad? That is her speech for tomorrow you have torn up!”

“Have you gone mad?” He shook her away. “You were going to let her read that . . . that insult to her teachers?”

“Insult to her teachers!” My mother’s face had crumpled up like a piece of paper. On it was written a love note to my father. Ever since they had come to this country, their life together was a constant war. “This is America, Papi, America!” she reminded him now. “You are not in a savage country any more!”

I was on my knees, weeping wildly, collecting all the little pieces of my speech, hoping that I could put it back together before the assembly tomorrow morning. But not even a sibyl could have made sense of all those scattered pieces of paper. All hope was lost. “He broke it, he broke it,” I moaned as I picked up a handful of pieces.

Probably, if I had thought a moment about it, I would not have done what I did next. I would have realized my father had lost brothers and comrades to the dictator Trujillo. For the rest of his life, he would be haunted by blood in the streets and late night disappearances. Even after he had been in the states for years, he jumped if a black Volkswagen passed him on the street. He feared anyone in uniform: the meter maid giving out parking tickets, a museum guard approaching to tell him not to touch his favorite Goya at the Metropolitan.

I took a handful of the scraps I had gathered, stood up, and hurled them in his face. “Chapita!” I said in a low, ugly whisper. “You’re just another Chapita!”

It took my father only a moment to register the hated nickname of our dictator, and he was after me. Down the halls we raced, but I was quicker than he and made it to my room just in time to lock the door as my father threw his weight against it. He called down curses on my head, ordered me on his authority as my father to open that door this very instant! He throttled that doorknob, but all to no avail. My mother’s love of gadgets saved my hide that night. She had hired a locksmith to install good locks on all the bedroom doors after our house had been broken into while we were away the previous summer. In case burglars broke in again, and we were in the house, they’d have a second round of locks to contend with before they got to us.

“Eduardo,” she tried to calm him down. “Don’t you ruin my new locks.”

He finally did calm down, his anger spent. I heard their footsteps retreating down the hall. I heard their door close, the clicking of their lock. Then, muffled voices, my mother’s peaking in anger, in persuasion, my father’s deep murmurs of explanation and of self-defense. At last, the house fell silent, before I heard, far off, the gun blasts and explosions, the serious, self-important voices of newscasters reporting their TV war.

A little while later, there was a quiet knock at my door, followed by a tentative attempt at the doorknob. “Cukita?” my mother whispered. “Open up, Cukita.”

“Go away,” I wailed, but we both knew I was glad she was there, and I needed only a moment’s protest to save face before opening that door.

What we ended up doing that night was putting together a speech at the last moment. Two brief pages of stale compliments and the polite commonplaces on teachers, wrought by necessity without much invention by mother for daughter late into the night in the basement on the pad of paper and with the same pencil she had once used for her own inventions, for I was too upset to compose the speech myself. After it was drafted, she typed it up while I stood by, correcting her misnomers and mis-sayings.

She was so very proud of herself when I came home the next day with the success story of the assembly. The nuns had been flattered, the audience had stood up and given “our devoted teachers a standing ovation,” what my mother had suggested they do at the end of my speech.

She clapped her hands together as I recreated the moment for her. “I stole that from your father’s speech, remember? Remember how he put that in at the end?” She quoted him in Spanish, then translated for me into English.

That night, I watched him from the upstairs hall window where I’d retreated the minute I heard his car pull up in front of our house. Slowly, my father came up the driveway, a grim expression on his face as he grappled with a large, heavy cardboard box. At the front door, he set the package down carefully and patted all his pockets for his house keys —precisely why my mother had invented her ticking key chain. I heard the snapping open of the locks downstairs. Heard as he struggled to maneuver the box through the narrow doorway. Then, he called my name several times. But I would not answer him.

“My daughter, your father, he love you very much,” he explained from the bottom of the stairs. “He just want to protect you.” Finally, my mother came up and pleaded with me to go down and reconcile with him. “Your father did not mean to harm. You must pardon him. Always it is better to let bygones be forgotten, no?”

I guess she was right. Downstairs, I found him setting up a brand new electric typewriter on the kitchen table. It was even better than the one I’d been begging to get like my mother’s. My father had outdone himself with all the extra features: a plastic carrying case with my initials, in decals, below the handle, a brace to lift the paper upright while I typed, an erase cartridge, an automatic margin tab, a plastic hood like a toaster cover to keep the dust away. Not even my mother, I think, could have invented such a machine!

But her inventing days were over just as mine were starting up with my schoolwide success. That’s why I’ve always thought of that speech my mother wrote for me as her last invention rather than the suitcase rollers everyone else in the family remembers. It was as if she had passed on to me her pencil and pad and said, “Okay, Cukita, here’s the buck. You give it a shot.”

Data & Analysis Sheet

Name: Matthew Woods

Part 1: Vinegar reacting with calcium carbonate in eggshells

1. Describe what you saw each time you stirred the mixtures, including final observations of each.

In Cup 1, I didn’t see much just a couple bubble here and there. In Cup 2, over time I saw the egg get bigger and feels rubbery and flexible with a lot more bubbles forming than Cup 1.

2. In words only, write the chemical reaction occurring when vinegar and the eggshell react. It’s similar to Equation #7 in the instructions (but just use words, not formulas). Here’s the beginning: “Calcium carbonate plus acetic acid react to yield….”

Calcium Carbonate (CaCO3) and acetic acid (CH3COO) reacts in a double replacement reaction, giving you calcium acetate, water, and carbon dioxide. Since calcium acetate is soluble it’ll dissolve. This leaves behind the egg’s inner membrane, making it flexible and rubbery. 

3. What gas is in the bubbles produced? carbon dioxide gas

4. In Cup 1, what is the limiting reactant and what evidence do you have to support your claim?

5. In Cup 2, what is the limiting reactant and what evidence do you have to support your claim?

Part 2: Experimental Data for Baking Soda and vinegar reacting

Part 2: Table for Calculation Results (Show work below this table and enter final results here)

Be careful of sig fig in your measurements and calculations.

Calculations (Show all work by each question below and then enter the final results of each calculation into the table above.) Please make your answers stand out by bolding or coloring them.

6. Determine the molar mass of sodium bicarbonate.

Molar mass of NaHCO3 = 84.00661 g/mol

22.989770+1.00794+12.0107+15.9994*3

Sig figs = 84.0 g/mol

7. Calculate the number of moles of sodium bicarbonate using the mass of baking soda.

8. Determine the mass of acetic acid used in the experiment. You need to look on your bottle of vinegar to do this. If your vinegar is 4 %, this means that every 100 g of vinegar contains 4 g of acetic acid. (If it is 5 %, then 100 g contains 5 g of acetic acid). To calculate the mass of acetic acid, use the following equation. For 5 %, replace 0.04 with 0.050. Record results in table. You can assume the percent has 2 sig figs.

mass of acetic acid = mass of vinegar x 0.040

9. Determine the molar mass of acetic acid, HC2H3O2.

10. Determine the number of moles of acetic acid in each sample of vinegar. Hint: you need to use the mass of acetic acid, not the mass of vinegar.

11. Add the mass of baking soda and vinegar initially. This is the total initial mass of reactants.

12. Record the final mass of mixture.

13. Determine the total mass gain or loss for the reaction by comparing your initial mass to the final mass of mixture. This is the mass of carbon dioxide lost which is your actual loss.

14. Compare the moles of sodium bicarbonate to moles of acetic acid. Which one is the limiting reactant and why? Show calculations to support this but also describe what you saw that supports your statement.

15. Determine the number of grams of carbon dioxide that the reaction should theoretically produce. This is where the pen and paper stoichiometry comes in. In the calculation, use the limiting reactant as your “known” and the carbon dioxide as your unknown. You have already calculated the moles of sodium bicarbonate and acetic acid used so Step I in the “three steps process” used to go from grams known to grams unknown is already done. See the Ch. 8 Lecture about Steps II and III, remembering that one mole of acetic acid or sodium bicarbonate should produce one mole of carbon dioxide (from Eq #7).

16. Calculate the “percent yield” for the carbon dioxide produced. If the actual yield is a negative number, then the % yield would be 0.

Be careful of sig figs in your calculations. Make sure you showed work.

Questions

17. Look at the percent yield of carbon dioxide produced. Give a possible cause (experimental error, not calculation or measurement or instrumental error) for differences between what you calculated should be produced (theoretical yield) and what was actually produced. This should be something that you probably couldn’t avoid very well. (So don’t say, “I measured wrong” or “I calculated wrong” because this is easily avoidable by redoing the lab or re-measuring).

18. In the calculation for #15, why couldn’t the moles of the other reactant be used in the calculation?

19. True or False: After you figure out the moles of the reactants in a reaction, the lower amount of moles is always the limiting reactant. Please explain your answer thoroughly. Providing an example would be very helpful.

Keep going on the next page

Extension with calcium carbonate :

Suppose we did the quantitative experiment part 2 with calcium carbonate (found in egg shells and Tums) instead of baking soda. So we reacted it with vinegar and took mass measurements.

20. Write a balanced reaction for acetic acid reacting with calcium carbonate. Be careful. It is no longer a 1:1 ratio. Hint: you should’ve written this in words in #2 so now turn those words into correct formulas and balance. Include phases.

21. Suppose we got the following data from doing the lab with vinegar and calcium carbonate. Fill in the 2 missing boxes (with the green stars **) using the given data.

Calculations (Show all work by each question below the table and then enter the final results of each calculation into the following table)

22. Determine the molar mass of calcium carbonate (using a periodic table).

23. Calculate the number of moles of calcium carbonate using the data above.

24. Determine the mass of acetic acid used in the experiment. Assume vinegar is 5% on the bottle. (If it is 5 %, then 100 g contains 5 g of acetic acid). Record results in table below. You can assume the percent has 2 sig figs.

25. Determine the molar mass of acetic acid, HC2H3O2. No need to show work here if you did above. Just put it in the table.

26. Determine the number of moles of acetic acid in the sample of vinegar that was used. Hint: you need to use the mass of acetic acid, not the mass of vinegar.

27. Add the mass of calcium carbonate and vinegar initially. This is the total initial mass of mixture. Record results.

28. The final mass of the mixture is given in the table above. Just report this number below (no work to show).

29. Determine the total mass gain or loss for the reaction by comparing your initial mass to the final mass of mixture. This is the mass of carbon dioxide lost which is your actual loss.

30. To determine the number of grams of carbon dioxide that the reaction should theoretically be produced, we need to first determine the limiting reactant. This is where the pen and paper stoichiometry comes in. Compare the moles of calcium carbonate to acetic acid. Which one is the limiting reactant and why? ** Be very careful** This is not a 1:1 ratio like the first part of the lab.

31. Determine the theoretical yield of carbon dioxide. To do this, in the calculation, use the limiting reactant as your known and the carbon dioxide as your unknown. You have already calculated the moles of calcium carbonate and acetic acid used so Step I in the “three steps process” used to go from grams known to grams unknown is already done. See the Ch. 8 Lecture about Steps II and III, but remember that now we do not have a 1:1 ratio.

32. Calculate the “percent yield” for the carbon dioxide produced. If the actual yield is a negative number, then the % yield would be 0.

Extra Credit Questions:

a) In this particular example, the change in mass during the reaction provides evidence that a chemical reaction is taking place. Explain this.

b) Is it necessary to have a change in mass in order to have a chemical reaction? Why or why not?

c) Provide an example of a chemical reaction (not just a physical change) where no mass change would be observed.

Engineering a Better Airbag Student Name Date

Data

Data Table 1: Model Air Bag

Data Table 2: Model Air Bag

Data Table 3: 80-L Driver-Side Air Bag

Data Table 4: 160-L Front Passenger-Side Air Bag

1. Based upon the observed performance of the air bag models and the amounts of sodium bicarbonate and acetic acid (vinegar) needed for an automotive air bag of 80 or 160 L, are these reactants a good substitute for sodium azide? One additional note regarding sodium azide: the rate of inflation after a triggering impact is 40 milliseconds (0.04 s).

© 2016 Carolina Biological Supply Company