Question

69. What volume of each of the following acids will react completely with 50.00 mL of 0.200 M NaOH? a. 0.100 M HCI b. 0.150 M HNO3 c. 0.200 M HC2H302 (1 acidic hydrogen)

Answer 1

Here we have to understand that, what exactly the term "the base completely react with the acids" mean. A base of a given concentration, do react completely with an acid of a given concentration when

the number of moles of the base = the number of moles of acid!

The point in the graph, where this situation takes place is called the equivalence point.

So, it is clear from the above point that, all we have to find the volume of the acid at the equivalence point!

As each of the acids will react in ratio with NaOH, we can simply go on and use the
VASA VBSB
equation, where,

$V_{A}$ - Volume of acid required in each case = ?

$S_{A}$ - Strength/ concentration of the acids

$V_{B}$ - Volume of the base = $50mL=0.05L$

$S_{B}$ - Strength/ Concentration of the base =

Now, by using this equation, we are actually equating the number of moles of acid to the base as-

$Volume (in L)\times Concentration(in M)=moles$,

which is the case at the equivalence point, and thus finding the $V_{A}$ .

07 In this : . VA = case, SA= 0.1 MHC No. SB 0.05L x 0.264) SA Ilms NA = 0.1 L loom L. Hel. o In this case, case, SA = 0.15(M) HNO3 : VA NA = NB.SB SA D 0.05 L x 0.2 رانا c7 -> VA = = 0.0666L 0.156) Hnos NA = 0.0666L Hnoz = 66.6 on L Haos here, Hore SA = 0.2(M) HC2H302 For forest H-ionization, 0.05LX0.2(M) NA 0.05L 2 (M) VA= 0.05 La 50mL of HeaH302