Brewer Science 3.08

Which mixture is paired with the best tool for separating the materials?

• Salt and Pepper - Tweezers

• Pieces of cork and pebbles - Beaker of water

• Safety pins and iron nails - Magnet

• Sand and iron filings - Colander

Which procedure best explains how to separate a mixture of salt, iron filings, and water without using their hands?

• Pull out the iron filings with a magnet. Pour the mixture through a coffee filter.

• Freeze the mixture. Chip away the iron filings.

• Pull out the iron filings with a magnet. Add heat to the mixture and allow the water to evaporate.

• Pour the mixture through a coffee filter. Pull out the iron filings with a magnet.

A student is given a beaker containing powdered drink mix and water. Which of these ways could the student use to separate the powdered drink mix from the water?

• 1. 1. Boil the mixture to evaporate the water

• 2. 2. Pass a magnet over the mixture

• 3. 3. Pour the mixture through a paper filter

• 4. 4. Use tweezers

A student made a mixture using equal amounts of salt and pepper. The salt grains were the same size as the pepper grains. What should the student do to most easily separate the pepper from the salt?

• Put the mixture in water and filter the pepper out of the water.

• Run a small magnet through the mixture to attract the pepper.

• Use a pair of tweezers to remove each grain of pepper.

• Use a strainer with a fine wire screen to remove the pepper.

A student combined powdered paint with water to make a small amount of blue liquid paint mixture. The student left the paint mixture in an open container. Several days later the student found the container and observed that changes had occurred. What most likely happened to the mixture?

• The container was empty after the mixture evaporated into the air.

• The paint evaporated, leaving only clear water in the container.

• The water evaporated, leaving only dry blue solid in the container.

• The liquid paint mixture was lighter in color after some water evaporated.