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 250cm³ of solution.

FA2; which is 0.05M hydrochloric acid.

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

Procedure

1. Pipette 25cm³ of 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

Burette reading	1	2	3
Final reading/cm3
Initial reading/cm3
Volume 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:

Burette reading	1	2	3
Final reading/cm3
Initial reading/cm3
Volume used/cm3

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.