Chemistry revision S3 Flashcards
What is chromatography
Chromatography can be used to separate mixtures of coloured compounds. Mixtures that are suitable for separation by chromatography include inks, dyes and colouring agents in food.
What is RF values in chromatography
Different chromatograms and the separated components of the mixtures can be identified by calculating the Rf value using the equation:
Rf = distance moved by the compound ÷ distance moved by the solvent
The Rf value of a particular compound is always the same - if the chromatography has been carried out in the same way. This allows industry to use chromatography to identify compounds in mixtures.
What is the reactivity of metals in copper sulphate solution
For example, magnesium is more reactive than copper.
When a piece of magnesium is dipped into blue copper sulfate solution:
the blue colour fades as colourless magnesium sulfate solution forms
brown copper coats the surface of the magnesium
What is the reactivity of metals in iron sulphate solution
Acids like iron react with most metals and when they do, a salt is produced. But unlike the reaction between acids and bases, we do not get water. Instead we get hydrogen gas.
What is the word and symbol equation for copper sulphate
The word and symbol equation for copper is CuSO4
What is the word and symbol equation for iron sulphate
The word and symbol equation for iron sulphate is FESO4
What is distillation
Distillation is the process in which the components of a substance or liquid mixture are separated by heating it to a certain temperature and condensing the resulting vapors.
What is fractional distillation
Fractional distillation is the separation of volatile components of different boiling points in a mixture by the gradual increase of temperature and the separate collection of each component.
What is the particles in the nucleus of an atom
Protons and neutrons are bound together to form a nucleus by the nuclear force.
Almost all of the mass of an atom is located in the nucleus, with a very small contribution from the electron cloud
Whats the reactivity of lithium, sodium and potassium in The Reactivity Series.
Lithium- Fizzes steadily, gradually disappears
Sodium- Fizzes rapidly, melts into a ball and disappears quickly
Potassium- Ignites with sparks and a lilac flame, disappears very quickly
Whats the reactivity series
In the reactivity series, the most reactive element is placed at the top and the least reactive element at the bottom. More reactive metals have a greater tendency to lose electrons and form positive ions.
