Practice Problem: Gravimetric Analysis

The video tutorial explains a gravimetric analysis problem involving a solid mixture containing calcium sulfate. The mixture is dissolved and treated with barium nitrate, resulting in barium sulfate precipitation. The tutorial guides through the stoichiometry calculations to determine the mass of calcium sulfate that reacted and calculates its percentage in the original mixture.

What is the main objective of the gravimetric analysis problem introduced in the video?

• To measure the density of barium nitrate

• To calculate the solubility of calcium sulfate

• To find the percentage of calcium sulfate in a solid mixture

• To determine the molar mass of barium sulfate

Why is it necessary to convert the mass of barium sulfate to moles during stoichiometry?

• Because mass is not a reliable measurement

• Because moles allow for direct comparison in chemical reactions

• Because moles are a unit of volume

• Because moles are easier to measure

What is the molar mass of barium sulfate used in the stoichiometry calculations?

• 0.6168 grams per mole

• 233.38 grams per mole

• 0.4550 grams per mole

• 136.14 grams per mole

How is the mass of calcium sulfate in the solution determined?

• By calculating the density of the solution

• By using the moles of barium sulfate precipitate

• By using the initial mass of the solid mixture

• By measuring the volume of the solution

What percentage of the original solid mixture was found to be calcium sulfate?

• 50.00%

• 25.00%

• 79.08%

• 100.00%