Mixtures
What is a mixture?
A combination of two or more substances that can be separated.
Oil and water are combined. Do they keep their physical properties?
Yes. Oil and water maintain their physical properties and can separate.
A student removes raisins from trail mix. What happens to the other ingredients?
Their physical properties do not change.
Which is a mixture: saltwater or pretzels and nuts?
Pretzels and nuts
A mixture contains sand, gravel, and fertilizer pellets. What can you predict will happen to the substances?
The substances remain separate and keep their physical properties.
What is a solution?
A mixture in which substances spread evenly and cannot be distinguished from one another.
What does dissolve mean?
To break down a substance in a liquid.
Which is a solution: sand and water or sugar and water?
Sugar and water.
Is soil and water a solution?
No. Soil and water form a mixture, but the soil does not dissolve evenly.
What happens to salt when it dissolves in water?
The salt spreads evenly throughout the water and cannot be seen separately.
What is a physical property?
An observable, measurable, or testable characteristic of matter.
What does maintain mean?
To stay the same.
A fruit salad is separated. Do the fruits keep their physical properties?
Yes. Their physical properties are conserved.
When oil and water separate after sitting, what does this tell us?
They maintained their physical properties, otherwise known as a mixture.
A student mixes red beads, blue beads, and yellow beads in a container. What can the student predict about the beads after they are mixed?
The beads will maintain their physical properties, such as their color and size, because mixing them does not create a new substance.
What tool separates iron filings from sand?
A magnet
What tool separates gravel from sand?
A sieve.
What method separates a solid from a liquid, such as sand from water?
A filter, such as a coffee filter.
What happens to water during evaporation?
It changes into a gas and leaves the mixture.
A wheelbarrow has soil and water. After lots of sunshine, what remains?
The water evaporates and the soil remains.
Why does oil float on water?
Water is denser than oil.
Which TWO can be separated from recycling trash with a magnet: paper clips, plastic bags, iron nails, cardboard?
Paper clips and iron nails.
A mixture has gravel, sand, and water. Which tool could remove the gravel first?
Tweezers or a sieve.
Which TWO maintain their physical properties when mixed with water: sugar, sand, iron filings, salt?
Sand and iron filings
If substances in a mixture can still be identified and separated, are they likely to have formed a new substance?
No. They are a mixture and their physical properties can be conserved.