Solutions and Suspension

Big Idea:  Solutions and Suspension

Focus question:  What is the difference between a solution and a suspension? (chart) How could we separate the unknowns from the water mixture?

Prediction:  If we add a lot of water to our unknowns, then we will not be able to see the two parts.

Planning:  1) Fill each plastic cup to the 5 mL line. 2) Add 3 spoonfuls (stirring after each) of each unknown to each cup of water. Place the color dot to match the unknown’s color. 3) Observe closely. Record your findings and questions on your charts.

               

Data :  What Did We Observe?

(Color, change, texture, odor change—science properties)

Suspension—can see the parts   Solution—can’t see the parts 

Red	Before:  can still see particles (suspension)
	After:  still wet, still crystalized, hardened, still didn’t dissolve—mixture was separated,
Yellow	Before: cloudy (suspension)
	After: unknown went through filter and into dish, powdery inside filter
Green	Before: not dissolving, sticking to sides of cup (solution)
	After:  flaky, looks like dried/flaky paint, water evaporated
Blue	Before:  not completely dissolving, (suspension)
	After:  solid, brittle—breaks when pressed, like a sand dollar
Orange	Before:  milky, cloudy, not dissolving (Solution)
	After:  crumbly at the bottom, pasted on the side

  

Claims and evidence:

We found that liquid chemicals can cause our unknowns to change color, shape, and texture. We found that liquid separated from the mixtures. We know that because the liquid was in the containers under the filter, or disappeared.

Conclusion/Reflection:  1) Evaporation caused the water to leave. 2) Crystals formed by evaporation and filtration.

Questions:  What will happen to our boiling water and sugar?

Literacy Connections:  Using the “The Crystal Story,” discuss growing sugar crystals with boiling water and sugar.