Question

when will temerature changes occur in the first part of the experiment?

EXPERIMENT 4: POSTLAB EXERCISE Name Assume vou have a mixture of two types of plastic and need to separate them You know that plastic A and B are both white in color, plastic A will dissolve in toluene and plastic B will not; plastic A has a density of 0.57 g/cm' and plastic B has a density of 1.08 g/em Oh, by the way, your boss, wants all of both plastics in the original shape. How would you separate these two plastic samples based on the information given? 1 C.E78 P-1-0% Indicate which of the following mixtures are heterogeneous. 2. salt dissolved in water mixture of sand and salt 7-UP Sugar water stainless steel alloy Italian salad dressing fog milk smoke copper ore Indicate which type of separation technique might be useful in the following mixtures Use the appropriate letter codes as: C- centrifugation, E- extraction, F - filtration, P- precipitation. 3 muddy water dye solution salt in water copper ore paint pigment/solvent paper pulp solution 83

Answer 1

1) Plastic A has a density of 0.57 g/cm³ and soluble in toluene

Plastic B has a density of 1.08 g/cm³ and insoluble in toluene

Toluene density = 0.87 g/cm³

These plastics can be separated using different kind of solutions.

Plastics will float when it is less denser than the solvent used whereas it sinks when it is more denser than the solvents.

As plastic A is soluble in toluene, this shows that it non polar in nature as it soluble in organic solvent.

Hence solvent like water whose density is 1 g/cm³ can be used for separation of Plastic A in its original state as it is less dense then water.

Toluene can be used to separate plastic B as it is insoluble in it this shows that plastic B is polar in nature, so water cannot be used to separate it.

It sinks to the bottom as it is heavier than the toluene or it can be separated using solvent whose density is heavier than the plastic B where it floats.

2) Salt dissolved in water (soluble) - so homogenous

b) Mixture of sand and salt - heterogenous not soluble

c) 7-UP - Homogenous mixture because carbonated bubbles are soluble in water

d) Sugar water - homogenous mixture because sugar is soluble

e) Italian salad dressing - heterogenous mixture it's not like solution

f) Stainless steel alloy - Homogenous mixture which contains iron, carbon , nickel and other components into one form

g) Milk - Heterogenous mixture as many fats are not soluble

h) fog - Heterogenous mixture because many of the components are not soluble and looks like colloid

I) copper ore - Heterogenous mixture because it is mixture of components which are not soluble

j) smoke - Heterogenous mixture because its components can be filtered

3) Dye solution - Can be separated by solvent extraction / evaporation/chromatographic techniques

b) Muddy water - Can be separated by filtration

c) Copper ore - Can be separated by extraction

d) Salt in water - Can be separated by precipitation /evaporation/electrodialysis/ distillation

e) Paint pigment/solvent - Can be separated by centrifugation

f) Paper pulp solution - Can be separated by centrifugation