User:Enalumenya/Temp/PRACTICAL CHEMISTRY S.5 JULY 2010.doc

''' PRACTICAL CHEMISTRY

INSTRUCTIONS: Answer all questions in the spaces provided.

You are provided with the following solutions:

FA1 ; which contains a mixture of sodiumhydroxide and anhydrous sodiumcarbonate per 250cm 3 of solution.

FA2 ; which is 0.05M hydrochloric acid.

You are required to determine the composition by mass of FA1.

Procedure


 * 1) Pipette 25cm3of FA1 into a conical flask and titrate with FA2 using phenolphthalein as indicator. Repeat the titration two times and record your results in the table below:

Results

Volume of pipette used = …………………cm3

Average volume used =


 * 1) Pipette 25cm3 of FA1 into a conical flask and titrate with FA2 using methylorange as indicator. Repeat the titration two times and record your results in the table below:

Average volume used =

Calculations (Na = 23; C = 12; O = 16; H = 1)


 * 1) Deduce the volume of hydrochloric acid required for complete neutralization of:


 * 1) Sodiumcarbonate


 * 1) Sodiumhydroxide

(b) Determine the composition by mass of FA1.