Virtual Lab Giter paper with the precipitate is first incinerated on a Bunsen bu

Question

Virtual Lab Giter paper with the precipitate is first incinerated on a Bunsen burner by a low flame and then transferred to an etectric burner ·Observation: Observations of Experimental Procedure In this section, make observations for every step of the procedure The given barium chloride solution is made up to 100ml. in a standard flask. The crucible is transferred to desiccator and cooled Observation . When cold, the crucible is weighed. . 20ml of solution is pipetted into a 250 mL beaker Heating, cooling and weighing are repeated till concordant values are obtained Observation: bout SmL 2N HC is added and diluted to 150mL with distilled water Observation Calculation Mass of crucible ld -(a) s Mass of crucible lid + Barium sulfate (b)g . The solution is heated to boiling and a hot solution of 4N H:SOs (10 15mL) is added drop by drop with constant stirring till the precipitation is complete Observation . Th . Observation: e solution containing the precipitate is heated in a water bath for 5 minutes Mass of Barium sulfate (b-a) g ·The precipitate is allowed to stand for an hour 233.36g of barium sulfate contain 137.36 g of barium Mass of barium in (b-a) g of Barium sulfate Therefore, Mass of Barium in the whole of the given solution The clear solution is decanted through an ashless filter paper (whatman No. 40) . The precipitate is washed with hot distlled water to free sulfate ions. ·Observation: ·The particles adhering to the sides of the beaker and glass rod are removed hy policeman. Observation: . Finally the precipitate is washed once again. " Observation: Result: The dried filter paper is folded and placed in a crucible which has been previously Mass of Barium in the whole of the given solution weighed. . Observation

Explanation / Answer

Analysis of barium

Here, barium analysis is done by converting the barium to barium sulfate precipitate

The chemical reaction occuring would be,

Ba2+ (aq) + H2SO4 (aq) ---> BaSO4 (ppt) + 2H+ (aq)

The precipitated BaSO4 is incinerated in oven and the mass of final precipitate is obtained.

1 mole of Ba2+ would give 1 mole of BaSO4 formation

Observation : The precipitate is obtained as white solid.

moles of BaSO4 formed = final mass of BaSO4 precipitate/233.36 g/mol

moles of barium (Ba2+) = moles of BaSO4

mass of Barium in the sample = moles of Ba2+ x 137.36 g/mol

This mass obtained is for 20 ml sample

So,

Total mass of barium in the entire sample = mass of Barium from above x 100/20

[Formulas used, moles = grams/molar mass]

So feeding the values for the mass of precpitate obtained (starting with 20 ml sample solution) we can calculate the mass of barium in the original sample solution (100 ml).

Related Questions

Navigate

• Browse (All)
• Browse V
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.