Stu Dent does the ternary mixture separation. His results are 50 % NaCl, 37 % Si
ID: 937970 • Letter: S
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.
Explanation / Answer
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.