Topic 2- States of matters and mixtures Flashcards
What is a mixture?
A substance consisting of 2 or more elements or compounds not chemically combined together.
What is a pure substance?
A substance made from a single element or compound made from one type of particle
What is a pure substance when talked about daily?
A substance with nothing added/ unadulterated, e.g pure milk.
What is the difference between the melting/ boiling points of pure substances versus mixtures?
Pure substances change state at a specific temperature, whereas mixture change state over a range of temperatures as they consist of multiple elements.
How does simple distillation work?
1)Temperature is added, allowing one liquid evaporates first.
2) Vapour raises and is condensed back into a liquid in the condenser.
What is simple distillation used for?
To separate two substances with different boiling points. Usually ethanol and water.
What is the sequence of simple distilation?
Heating –> Evaporating–> cooling–> condensing
Explain how can simple distillation be improved?
1) Anti-bumping granules-prevents mixture from boiling over into the condenser meaning impurities won’t contaminate the product
How does chromatography work?
As the different colours range in how soluble they are, they will dissolve and therefore move up the paper at different rates, causing the colour separation.
What is the stationary phase in chromatography?
The paper
What is the mobile phase in chromatography?
The solvent
What is a solute?
The substance which dissolves
What is a solvent?
The liquid the solute dissolves in
Why is the baseline drawn in pencil?
Because for example ink would dissolve and move up the paper and interfere with the results.
Why must the solvent be put under the baseline?
The ink would dissolve into the liquid and not travel up the paper.
