Practice How Indicators Work (2.5.1) - Unit 8: Acids and Bases

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6 sample questions

Question 1.
What is the color change of Methyl Red in acidic conditions?
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Think about how the color looks in relation to pH.
Question 2.
What does an indicator represent in a chemical reaction?
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Consider what happens when you add acid or base.
3Question 3.
What happens to an indicator when the pH decreases?
- It changes to its base form
- It changes to its acid form
- It remains unchanged
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Think about how H plus ions influence the equilibrium.
4Question 4.
True or False: An indicator can only transition between two colors.
- True
- False
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Focus on the nature of acid-base indicators.
Question 5.
You have a weak acid indicator with a pKa of 4.5. What is the expected color change range for this indicator?
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Remember to use pKa ± 1.
Question 6.
A universal indicator shows a shift from red at pH 1 to purple at pH 14. What does this tell you about its usefulness?
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Consider what range has been covered by this indicator.

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