Problem 7.66 How many milliliters of 9.00 M KOH must be added to neutralize the
ID: 529245 • Letter: P
Question
Problem 7.66
How many milliliters of 9.00 M KOH must be added to neutralize the following solutions?
Part A
a mixture of 0.240 M LiOH (25.0 mL) and 0.200 M HBr (75.0 mL)
Express your answer with the appropriate units.
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Part B
a mixture of 0.300 M HCl (45.0 mL) and 0.250 M NaOH (10.0 mL)
Express your answer with the appropriate units.
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Problem 7.66
How many milliliters of 9.00 M KOH must be added to neutralize the following solutions?
Part A
a mixture of 0.240 M LiOH (25.0 mL) and 0.200 M HBr (75.0 mL)
Express your answer with the appropriate units.
VKOH =SubmitMy AnswersGive Up
Incorrect; Try Again; 4 attempts remaining
Part B
a mixture of 0.300 M HCl (45.0 mL) and 0.250 M NaOH (10.0 mL)
Express your answer with the appropriate units.
VKOH =SubmitMy AnswersGive Up
Explanation / Answer
Balanced equation:
LiOH + HBr = LiBr + H2O
Part A
Moles of LiOH = 25 x 0.24 /1000 = 0.006 Moles
Moles of HBr = 75 x 0.2 /1000 = 0.015 Moles
Moles of HBr after reacting with LiOH = 0.015 -0.006 = 0.009 Moles
Moles of KOH to be needed = 0.009 Moles
Volume of KOH = 0.009 x 1000 /9 = 1 ml
Hence 1 ml of KOH is needed
Part B
Moles of HCl = 0.3 x 45 /1000 = 0.0135 Moles
Moles of NaOH = 0.25 x 10 / 1000 = 0.0025 Moles
Moles of HCl after reacting with NaOH = 0.0135 - 0.0025 = 0.011 Moles
Moles of KOH = 0.011 Moles
Volume of KOH = 0.011 x 1000 /9 = 1.2 ml
1.2 ml of KOH is needed