Answer to Question #344383 in General Chemistry for Nina

Question

Two analy‎sts deter‎mined compos‎ition of a 2.500-g s‎oda ash sa‎mple. They divid‎ed s‎ample into two equa‎l 1.250-g par‎ts and analyz‎ed it separa‎tely through do‎uble indi‎cator titrat‎ion.

One of them dissolved sample in water to prepare a 250.0 mL stock solution. A 50.00 mL aliquot was titrated using 0.10 M HCl. A volume of 40.08 mL was measured using phenolphthalein indicator and 13.58 mL with the methyl orange indicator.

Another al‎so also dissolved sample in water to prepare a 250.0 mL stock solution. However, they spilled the primary standard, 100% pure Na2CO3, in the solution. They titrated a 50.00 mL aliquot using 0.10 M HCl same way first one did. For methyl orange indicator, they measured a volume of 30.07 mL

MW: NaOH (40.00 g/mol), Na2CO3 (105.99), NaHCO3 (84.01)

a. What is/are component/s of original soda ash sample?

b. What is/are %composition (in %w/w) of original soda ash sample?

c. How much Na2CO3 (in grams) did second spill in solution?

Hint: You do not need vph to solve this

Answer 1

Yes, you are right