HMH Unit 2.2 Day Four pgs 118-120

HMH Unit 2.2 Day Four

Pgs 118-120

Separating Mixtures

• You now know that mixtures are combinations of matter where each thing still keeps its own properties.

• Think back to the salad earlier. What kinds of things did you see in this mixture? Now, imagine you want to remove all of the carrots and cucumbers from the rest of the salad. Are you able to do this easily?

Separating Mixtures

• Sometimes solutions need to be separated. There are several different ways this can be done. Some of these ways involve the use of advance equipment, while others use very simple methods.

Open Ended

The salad is made of different vegetables. How can these ingredients be separated?

Open Ended

The messy workbench can be sorted into metal and non-metal piles. How can you do this?

• When particles are mixed so well together that other separation methods don't work, sometimes scientist have to resort to very advanced techniques.

• An example is DNA. DNA is the part of your cells that carries the code for all of your traits.

• Since there is so much of it inside each cell, scientist need to separate different segments to be able to "read" it.

• They do this by sending electricity through a gel that has segments of DNA at one end. The different -sized segments travel different lengths along the shell, creating a DNA "fingerprint".

Paper Chromatography

• This is also a way to separate mixtures.

• This is used for pigments in different art supplies.

• You draw a line at the bottom of the paper, dip it just barley in the water and let the water climb up the paper. It will then separate out the ink that makes up that color.

Alloys

• You may think metals are strong, but most metals are really quite weak.

• It is only when they are mixed with other metals that they get their strength.

• When metals are mixed together, they form a new material, called an alloy.

Alloys

• Scientist and engineers use alloys when they design and build buildings.

• Alloys are thought of as a solution of metals. Stainless steel, pewter, and 18 carat gold are all examples of alloys.

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Open Ended

What is a mixture? Answer in complete sentences.

Open Ended

Why are solutions called "The best mixed mixtures"? Answer in complete sentences.