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Question
A buffer is prepared by combining 150 mL of 0.50 M NaOH and 250 mL of a 0.75 M weak acid, HA. If the pH of the buffer is 5.50, what is the Ka of the acid?
A.1.3 10-11
B.1.3 10-6
C.2.1 10-9
D.3.2 10-6
E.4.7 10-6
Answer
This answer is hidden. It contains 2 characters.
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Q:
What is the half-life of a first-order reaction if it takes 4.4 10-2 seconds for the concentration to decrease from 0.50 M to 0.20 M?A.2.5 10-2 sB.3.3 10-2 sC.1.6 sD.21 sE.27 s
Q:
Hydrogen peroxide decomposes into water and oxygen in a first-order process.
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Q:
A student analyzed a first-order reaction and obtained the graph below. Unfortunately, the student forgot to label the axes. What are the correct labels for the x and y axes? A.x axis = time, y axis = ln[A]
B.x axis = ln[time], y axis = [A]
C.x axis = ln[time], y axis = [A]
D.x axis = time, y axis = 1/[A]
E.x axis = 1/time, y axis = 1/[A]