Question

A 9.96 mL sample of nitric acid required 13.25 mL of 0.085 M strontium hydroxide for titration. Calculate the molarity of the acid solution. (Hint: It's stoichiometry, you need the balanced equation)

Answer 1

Answer:

The molarity of the acid solution = 0.226 M

Explanation:

Step 1: Data given

Volume of nitric acid = 9.96 mL = 0.00996 L

Volume strontium hydroxide = 13.25 mL = 0.01325 L

Molarity of strontium hydroxide = 0.085 M

Step 2: The balanced equation

2HNO3 + Sr(OH)2 → Sr(NO3)2 + 2H2O

For 2 moles HNO3 we need 1 mole of Sr(OH)2 to produce 1 mole Sr(NO3)2 and 2 moles H2O

Step 3: Calculate the molarity of the acid solution

n2 * C1 * V1 = n1*C2*V2

⇒ with n2 = the number of moles of Sr(OH)2 = 1 moles

⇒ with C1 = the molarity of HNO3 = TO BE DETERMINED

⇒ with V1 = the volume of HNO3 = 0.00996 L

⇒ with n1 = the number of moles of HNO3 = 2 moles

⇒ with C2 = the molarity of Sr(OH)2 = 0.085 M

⇒ with V2 = the volume of Sr(OH)2 = 0.01325 L

1*C1 * 0.00996 L = 2 * 0.085 M * 0.01325 L

C1 = (2*0.085*0.01325) / 0.00996

C1 =  0.226 M

The molarity of the acid solution = 0.226 M

Answer 2

Taking into account the reaction stoichiometry and molarity, the molarity of the acid solution is 0.2261 $\frac{moles}{liter}$.

Reaction stoichiometry

In first place, the balanced reaction is:

2 HNO₃ + Sr(OH)₂ → Sr(NO₃)₂ + 2 H₂O

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

• HNO₃: 2 moles
• Sr(OH)₂: 1 mole
• Sr(NO₃)₂: 1 mole
• H₂O: 2 moles

Definition of molarity

Molar concentration or molarity is a measure of the concentration of a solute in a solution and indicates the number of moles of solute that are dissolved in a given volume.

The molarity of a solution is calculated by dividing the moles of solute by the volume of the solution:

$Molarity= \frac{number of moles of solute}{volume}$

Molarity is expressed in units $\frac{moles}{liter}$.

Moles of strontium hydroxide required

In this case, you know:

• Molarity= 0.085 M
• number of moles of strontium hydroxide= ?
• volume= 13.25 mL= 0.01325 L (being 1000 mL= 1 L)

Replacing in the definition of molarity:

$0.085 M= \frac{number of moles of strontium hydroxide}{0.01325 L}$

Solving:

number of moles of strontium hydroxide= 0.085 M× 0.01325 L

number of moles of strontium hydroxide=0.001126 moles

Then, 0.001126 moles of strontium hydroxide are required.

Moles of nitric acid required

The following rule of three can be applied: If by reaction stoichiometry 1 mole of Sr(OH)₂ react with 2 moles of HNO₃, 0.001126 moles of Sr(OH)₂ react with how many moles of HNO₃?

$amount of moles of HNO_{3} =\frac{0.001126 moles of Sr(OH)_{2}x2 moles of HNO_{3} }{1 mole of Sr(OH)_{2}}$

amount of moles of HNO₃= 0.002252 moles

So, 0.002252 moles of nitric acid are required.

Molarity of the acid solution

In this case, you know:

• Molarity= ?
• number of moles of nitric acid= 0.002252 moles
• volume= 9.96 mL= 0.00996 L (being 1000 mL= 1 L)

Replacing in the definition of molarity:

$Molarity= \frac{0.002252 moles}{0.00996 L}$

Solving:

Molarity= 0.2261 $\frac{moles}{liter}$

Finally, the molarity of the acid solution is 0.2261 $\frac{moles}{liter}$.

Learn more about

the reaction stoichiometry:

brainly.com/question/24741074

brainly.com/question/24653699

molarity:

brainly.com/question/9324116

brainly.com/question/10608366

brainly.com/question/7429224