What type of reaction?HCl + NaOH H2O + NaCl

• A neutralization reaction is the reaction between an acid and a base to produce a salt plus water.

• A salt is any compound containing the cation of a base and an anion from an acid.– NaOH (base) -- Na+ cation– HCL (acid) -- Cl- anion– SALT -- NaCl

Episode 1103

Note: Salt is not always NaCl.

• Write the neutralization reaction when H2SO4 reacts with KOH. Label the acid, the base, and the salt.

H2SO4 + KOH + H2O K2SO42 2

acid base

salt

Episode 1103

Write the neutralization reaction when nitric acid reacts with magnesium hydroxide.

• Nitric acid– HNO3

• Magnesium hydroxide– Mg(OH)2

You know the products is going to be water and a salt• Formulate the salt• Write the equation and balance.

2HNO3 + Mg(OH)2 2H2O + Mg(NO3)2

Episode 1103

Titrations• A titration is a laboratory

method used to determine the concentration of an acid or base in solution by performing a neutralization reaction with a standard solution.

• In a neutral solution, the moles of hydrogen ions must be equal to the moles of hydroxide ions.

Episode 1103

• To find moles of [H+]– Moles H+ = (#moles H+/1 moleacid )(Macid)(Vacid)

• To find moles of [OH-]– Moles OH- = (#moles OH-/1 molebase )(Mbase)(Vbase)

• If neutral, moles of [H+] = [OH-]– (#moles H+/1 moleacid )(Macid)(Vacid) = (#moles OH-/1 molebase

)(Mbase)(Vbase)

Episode 1103

Find the molarity of a sample of HCl by neutralizing it with 0.5 M

NaOH.– Record volume of HCl solution.– Add indicator to HCl solution– Slowly add NaOH solution from burrette.

• The endpoint of a titration is the point at which the indicator changes color indicating the neutralization has been reached so the moles of hydrogen ions and moles of hydroxide ions are equal.– Record volume of NaOH solution added.

Episode 1103

Titration Calculation

(#moles H+/1 molea )(Ma)(Va) = (#moles OH-/1 moleb )(Mb)(Vb)

(1mol H+/1 mol HCl )(Ma)(50.0 mL) = (1 mol OH-/1 molNaOH )(0.5M)(20.2 ml)

(Ma)(50.0 mL) = (0.5M)(20.2 ml)

Ma = (0.5 M)(20.2 mL)/50.0 mL

Ma= 0.20 M HCl

Episode 1103

In a titration of HCl and KOH, 50.0 mL of the base were required to neutralize 10.0 mL of

a 3.0 M HCl. What is the molarity of the KOH?

(#moles H+/1 molea )(Ma)(Va) = (#moles OH-/1 moleb )(Mb)(Vb)

(1mol H+/1 mol HCl )(3.0M)(10.0 mL) = (1 mol OH-/1 molNaOH )(Mb)(50.0 ml)

(3.0M)(10.0 mL) = (Mb)(50.0 ml)

Mb = (3.0M)(10.0 mL)/50.0 mL

Mb= 0.60 M KOH

Episode 1103

60.0 mL of 0.50 molar NaOH were needed to neutralize 30.0 mL of H2SO4. What is the

molarity of the acid?

(#moles H+/1 molea )(Ma)(Va) = (#moles OH-/1 moleb )(Mb)(Vb)

(2mol H+/1 mol HCl )(Ma)(30.0 mL) = (1 mol OH-/1 molNaOH )(0.5M)(60.0 ml)

2(Ma)(30.0 mL) = (0.5M)(60.0 ml)

Ma = (0.5 M)(60.0 mL)/(2)(30.0 mL)

Ma= 0.50 M H2SO4

Episode 1103