Question

Stu Dent does the ternary mixture separation. His results are 50 % NaCl, 37 % SiO2, and 20 % CaCO3. The class average results are 33 % for each species.

Analyze Stu’s results – choose one or more items for each of his chemical species, making sure the explanations are actually physically possible.

NaCl increased – the solid is still wet.

NaCl increased – the solid is contaminated with CaCO3.

NaCl decreased – the solid is lost by “splattering”.

NaCl decreased – the solid partially evaporated.

SiO2 increased – the solid is still wet.

SiO2 increased – the solid is contaminated with CaCO3 SiO2 decreased – some solid spilled.

SiO2 decreased – some solid evaporated.

CaCO3 increased – the solid is contaminated with SiO2.

CaCO3 increased – the solid is still wet. CaCO3 decreased – the solid did not form completely.

CaCO3 decreased – the solid partially evaporated.

Answer 1

Separation of ternary mixture

NaCl, SiO2 and CaCO3

NaCl is increases : solid is wet

Presence of water would increase the final mass of NaCl obtained

NaCl decreases : solid lost by splattering

Lost solution containing NaCl in dissolved form would decrease final NaCl percentage.

SiO2 increases : solid is wet

Presence of water would increase the final mass of SiO2 obtained

SiO2 decreased : some solid spilled

CaCO3 increased : the solid is wet

CaCO3 decreased : the solid did not form completely.