QUIZ BEE - Group Activity

Because particles of colloidal dimensions scatter visible radiation, the path of the beam through the solution can be seen by the eye. What do you call this phenomenon?

• Colloidal Suspension

• Crystalline Suspension

• Tyndall Effect

• Precipitate

What mass of Cu(IO3)2 can be formed from 0.650 g of CuSO4 · 5H2O?

• 1.706 g Cu(IO2 )3

• 1.076 g Cu(IO3 )2

• 1.076 g Cu(IO2 )3

• 1.706 g Cu(IO3 )2

What mass of AgI can be produced from a 0.512-g sample that assays 20.1% AlI3?

• 0.718 g

• 0.817g

• 0.187 g

• 0.178 g

Which among the following is not a feature of Gravimetric Analysis?

• • A given analyte is isolated from the sample and weighed in some pure form.

• • Absolute analysis (no standard needed).

• • One of the most accurate and precise methods of macro quantitative analysis.

• • One of the newest methods known (before 1910).

Which among the following is not a factor that determines the particle size of precipitates?

• Rate at which reactants are mixed

• Solvent concentrations
  

• Temperature
  

• ppt solubility (Ksp)
  

It is a process by which a coagulated colloid returns to its dispersed state.

• Adsorption

• Peptization

• Absorption

• Precipitation

A 0.2121-g sample of an organic compound was burned in a stream of oxygen, and the CO2 produced was collected in a solution of barium hydroxide. Calculate the percentage of carbon in the sample if 0.6006 g of BaCO3 was formed.

• 12.73% C

• 17.32% C

• 17.23% C

• 12.37% C

Treatment of a 0.3500-g sample of impure potassium chloride with an excess of AgNO3 resulted in the formation of 0.2912 g of AgCl. Calculate the percentage of KCl in the sample.

• 60.59%

• 43.28%

• 60.95%

• 43.82%

An aqueous solution contains NaNO3 and KBr. The bromide ion is precipitated as AgBr by the addition of AgNO3. After an excess of the precipitating reagent has been added, what is the source of the charge?

• Na+ ions

• 3. Ag+ ions.
     

• 3. NO3– ions

• Br- ions

A 0.2356-g sample containing only NaCl (58.44 g/mol) and BaCl2 (208.23 g/mol) yielded 0.4637 g of dried AgCl (143.32 g/mol). Calculate the %NaCl compound in the sample.

• 44.99%

• 49.94%

• 55.01%

• 51.50%