Elements, Compounds & Mixtures
What is an element?
A substance made of only one type of atom.
What does filtering separate?
A solid from a liquid.
What does “soluble” mean?
Able to dissolve in a liquid.
What is a solvent?
The liquid that the solute dissolves in.
How can you tell a diagram shows a mixture?
It contains at least two types of atoms not chemically joined.
What is the residue in filtering?
The solid left behind in the filter paper.
In saltwater, what is the solute?
Salt.
What does “insoluble” mean?
A substance that cannot dissolve in a liquid.
What is the difference between a compound and a mixture?
A compound has atoms chemically joined; a mixture does not.
How does evaporation separate a solute from a solvent?
The solvent evaporates, leaving the solute behind.
What is the difference between dilute and concentrated solutions?
Dilute has little solute; concentrated has a lot of solute.
Why can magnets separate some mixtures?
Because magnetic materials can be pulled out using magnetic force.
Why can mixtures be separated more easily than compounds?
Because the substances in mixtures are not chemically bonded.
How does distillation separate liquids?
The liquid with the lower boiling point evaporates first and is condensed.
A student adds sugar until no more dissolves. What is the solution called?
A saturated solution.
Why does nail varnish dissolve in acetone but not in water?
nail varnish is soluble in acetone, not water.
A diagram shows two different molecules not bonded together. What is it?
A mixture, because the particles are not chemically joined.
Why do colours separate in chromatography?
They travel at different speeds in the solvent.
Why does temperature affect solubility?
Higher temperatures give particles more energy to dissolve.
Why do different dyes travel different distances in chromatography?
Because each dye has different solubility and attraction to the paper, causing them to move at different speeds.