Question

Consider the titration of a 26.1 −mL sample of 0.125 M RbOH with 0.110 M HCl. Determine each of the following.

Answer 1

Answer:

We're asked to find the molar concentration of the

NaCl

solution given some titration data.

Let's first write the chemical equation for this reaction:

NaOH

(

a

q

)

+

HCl

(

a

q

)

→

NaCl

(

a

q

)

+

H

2

O

(

l

)

Using the molarity equation, we can find the number of moles of

HCl

that reacted:

molarity

=

mol solute

L soln

mol solute

=

(

molarity

)

(

L soln

)

mol HCl

=

(

0.105

mol

L

)

(

0.0250

L

)

=

0.00263

mol HCl

(volume converted to liters)

Now, using the coefficients of the chemical reaction, we can determine the number of moles of

NaOH

that reacted:

0.00263

mol HCl

(

1

l

mol NaOH

1

mol HCl

)

=

0.00263

mol NaOH

Lastly, we'll use the molarity equation (using given volume of

NaOH soln

) again to determine the molarity of the sodium hydroxide solution:

molarity

=

mol solute

L soln

M

NaOH

=

0.00263

l

mol

0.315

l

L

=

0.00833

M

(volume converted to liters)