Question

Below are some of the steps completed in the titration process.

(i) Add base from the buret to the acid.
(ii) Transfer a known volume of acid to an Erlenmeyer flask.
(iii) Add three drops of chemical indicator to the acid.
(iv) Position the Erlenmeyer flask under the buret.

Which lists the steps in the correct order of occurrence?

A. i, ii, iii, iv
B. ii, iii, iv, i
C. iii, ii, i, iv
D. iv, iii, ii, i

Answer 1

Think about what your objective is in titration. You want to determine the molarity of your acid using the equation:
\(M_A V_A = M_B V_B \)
and the known information: V_A (measured volume of acid), M_B (known molarity of base), and V_B (difference between initial amount of base in buret and after the indicator changes color.

Steps (ii), (iii), and (iv) are all for set-up. Step (i) is beginning the titration process and must follow all the set-up steps. That eliminates choices A and C because they do not end with step (i).

Then for the logical order of the first three steps... we can't do (iv) -- putting the flask under buret -- until we've done (ii) and (iii) -- preparing the flask w/ known volume of acid and indicator. Are you able to figure out the answer from this information?

Answer 2

Yes, thank you @AccessDenied