Question

Patrick’s class is studying mixtures. The students hypothesized that if they mix two substances together a change will occur.

They divide into two groups. Each group had three plastic cups, three pieces of steel wool, water, and vegetable oil.

Each group followed these steps.


1. Put 2 ounces of water into one plastic cup.

2. Poured 2 ounces of vegetable oil in the second plastic cup.

3. Added one piece of steel wool to each cup.

4. Placed the third piece of steel wool into a dry plastic cup.

5. Covered each plastic cup loosely with plastic wrap.

6. Checked the cups every day for changes.

After two weeks, a red substance has formed on the steel wool in the water.

Write your responses in the space below.


Describe how the students made this a fair experiment; include the repeated trials used and the variables.

Answer 1

Answer:

This thermoforming technique begins with extruded or rolled plastic sheets of the desired thickness that are fed into a pre-heating machine. ... While in place the plastic is cooled until it reaches the desired rigidity. The final cover is ejected with reverse air flow before being trimmed or otherwise finished.