Calconcarboxylic acid

High school (ages 12+)
Science & Technology

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Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/calconcarboxylic-acid

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the IUPAC name?3-hydroxy-4-[(2-hydroxy-4-sulfonaphthalen-1-yl)diazenyl]naphthalene-2-carboxylic acid
2. What is the primary analytical use?Metallochromic indicator for complexometric titration of calcium with EDTA
3. How does Calconcarboxylic acid help scientists measure calcium?When it is in a solution with calcium, it turns blue by forming a complex. Adding EDTA removes the calcium, freeing the dye to turn pink, which shows the exact point of measurement.
4. Why does the color of Calconcarboxylic acid change?The color change happens when the dye goes from being bound to calcium to being free. This changes its electronic structure and produces a new color.

Metallochromic Indicator: A substance that changes color when it forms a complex with a metal ion.
Chelating Agent: A molecule that binds to metal ions, forming a stable ring structure.
Stoichiometric Equivalence Point: The point in a titration where the amount of titrant added is exactly enough to react with all of the analyte.