Question

Please enter the values you calculated for each of your three trials for the molarity of your NaOH solution. Place your molarity entries in the order corresponding with the masses of KHP and the volumes of NaOH required for the trials. You should enter 4 significant figures, e.g. 0.1487 M .
Entry # grams KHP mL NaOH M NaOH
#1: 0.5240 15.7 ?
#2: 0.5320 17.8 ?
#3: 0.5120 16.7

Answer 1

Answer:

#1. M NaOH = 0.1634 M

#2. M NaOH = 0.1464 M

#3. M NaOH = 0.1501 M

Explanation:

• molarity [=] mol/L

balanced reaction:

• NaOH + KHP → KNaP + H2O

∴ molar mass KHP = 204.22 g/mol

#1:

∴ mass KHP = 0.5240 g

∴ volume NaOH = 15.7 mL = 0.0157 L

⇒ moles NaOH = (0.5240 g KHP)(mol/204.22 g KHP)(mol NaOH/mol KHP)

⇒ moles NaOH = 2.566 E-3 mol

⇒ M NaOH = (2.566 E-3 mol)/(0.0157 L) = 0.1634 M

#2:

∴ mass KHP = 0.5320 g

∴ volume NaOH = 17.8 mL = 0.0178 L

⇒ moles NaOH = 2.605 E-3 mol

⇒ M NaOH = 0.1464 M

#3:

∴ mass KHP = 0.5120 g

∴ volume NaOH = 16.7 mL = 0.0167 L

⇒ moles NaOH = 2.5071 E-3 mol

⇒ M NaOH = 0.1501 M