QUESTION 2 An 20.00 mL unknown solution required two indicators for titration. The first indicator reaches its endpoint upon the addition of 10.00 mL 0.1000 M hydrochloric acid solution. Upon the addition of the second indicator, the solution automatically turned salmon pink without the addition of the standard acid solution. Analyze the problem and identify the concentration of the base in the solution. O 0.02500 M Na2c03 O 0.0.2500 M NaHCo3 0.05000 M NaOH 0.05000 M Na2cO3

QUESTION 2 An 20.00 mL unknown solution required two indicators for titration. The first indicator reaches its endpoint upon the addition of 10.00 mL 0.1000 M hydrochloric acid solution. Upon the addition of the second indicator, the solution automatically turned salmon pink without the addition of the standard acid solution. Analyze the problem and identify the concentration of the base in the solution. O 0.02500 M Na2c03 O 0.0.2500 M NaHCo3 0.05000 M NaOH 0.05000 M Na2cO3

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter11: Solutions

Section: Chapter Questions

Problem 26P

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What is an acidbase indicator? Define the equivalence (stoichiometric) point and the end point of a titration. Why should you choose an indicator so that the two points coincide? Do the pH values of the two points have to be within 0.01 pH unit of each other? Explain.
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Write the Lewis structures of the reactants and product of each of the following equations, and identify the Lewis acid and the Lewis base in each: (a) CS2+SHHCS3 (b) BF3+FBF4 (c) I+SnI2SnI3 (d) Al(OH)3+OHAl(OH)4 (e) F+SO3SFO3
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A friend asks the following: Consider a buffered solution made up of the weak acid HA and its salt NaA. If a strong base like NaOH is added, the HA reacts with the OH to form A. Thus the amount of acid (HA) is decreased, and the amount of base (A) is increased. Analogously, adding HCI to the buffered solution forms more of the acid (HA) by reacting with the base (A). Thus how can we claim that a buffered solution resists changes in the pH of the solution? How would you explain buffering to this friend?
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