Two graduate students in the Chemistry department were suspected of spilling the

Question

Two graduate students in the Chemistry department were suspected of spilling the acid without reporting it. Adam had been using 1.400 M HCl and Ben had been using 0.700 M HCl. A small amount of the acid was found in the bottom of the bottle near the scene. A 5.00 ml sample of the acid from the spill was titrated with sodium hydroxide and required 35.00 ml of 0.200 M NaOH to reach the equivalence point.

1. Write down the NET IONIC equation of the reaction between NaOH and HCl.

2. How many moles of NaOH were required to neutralize the acid?

3. Use your answers in 1 and 2 to determine how many moles of H+ were present in the 5.00 ml sample of acid.

4. What was the molarity of the spilled acid and hence who would you accuse?

Explanation / Answer

1)
Net ionic equation is:
H+ (aq) + OH- (aq)   ---> H2O (l)

2)
moles of NaOH = M(NaOH)*V(NaOH)
= 0.200 M * 0.0350 L
= 0.0070 mol

3)
mol of H+ = mol of OH-
= 0.0070 mol

4)
Molarity = number of mol of H+/ volume in L
= 0.0070 mol / 0.005 L
= 1.400 M

Adam should be accused

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.