A student is conducting molecular weight determination of an unknown diprotic acid. He first prepared a 250 mL of 0.15 M NaOH (39.997 g/mol) titrant solution, which he then standardized with 0.7625 g of KHP (204.22 g/mol) which consumed 26.32 mL of the titrant. After standardization, he weighed 0.0996 g of unknown diprotic acid and the titration reached the endpoint at a volume of 11.68 mL. What is the standardized concentration of titrant?

0.0710

Explanation:

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.