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What do we call an atom that has a positive or negative charge?
An ion
What are isotopes ?
An atom with the same number of protons but different number of neutrons
What is a solute ?
the minor component in a solution, dissolved in the solvent.
What is a solvent ?
any substance, usually liquid, which is capable of dissolving one or several substances, thus creating a solution.
What is a solution?
A homogenous type of mixture of two or more substances
How do you carry out the process if crystallisation?
First, pour the solution into an evaporating dish and heat it using a Bunsen burner.
Stop heating it when crystals start to form ('point of crystallisation') and allow it to cool down.
Then either leave it to allow the rest of the water to evaporate, or filter out the crystals using filter paper and a funnel. Lastly, dry the crystals in a warm oven.
What are the steps of simple distillation?
A solution is heated, usually using a Bunsen burner.
The liquid in the mixture evaporates into a gas.
The gas is cooled by a water jacket, and condenses into a liquid, which then flows into the beaker.
When Democritus first conceived of atomic theory, around 500 BC, how did he describe atoms?
Separated from each other by empty space
The smallest possible unit of matter
Small spheres
How did John Dalton describe the atom ?
In the 1800's, John Dalton described atoms as solid spheres, and suggested that different types of make up the different elements.
.
In 1897 J. J. Thomson theorised that an atom consisted of a ball of positive charge, with negative electrons mixed throughout it. What do we call this model?
The plum pudding model
How did Rutherford discover the nucleus?
In Rutherford's experiments, alpha particles were fired at a thin sheet of gold foil.
Most particles passed through, but some were deflected off course.
This caused him to hypothesise that there was a dense region of positive charge at the centre of the atom that repelled the alpha particles.
As a result he developed the nuclear model of the atom, in which there was a central positive nucleus, surround by negative electrons.
What did neil’s bohr discover?
That electrons orbit the atom in shells
Why do the reactivity of the group 1 metals increase as you go down the group ?
The reactivity of group 1 elements increases as you go down the group because the atoms become larger, which means that the outer electron becomes further from the nucleus.
This in turn means that the electrostatic attraction between the positive nucleus and the outer negative electron decreases in strength.
As a result the outer electron will be lost more easily, and so the element will be more reactive.
When alkali metals react with water what two products are formed ?
Alkali metals + water —>
What are the colours and physical states of the halogens at room temperature?
Fluorine is a poisonous yellow coloured gas and is the most reactive halogen
Chlorine is a green coloured gas.
Bromine is a red-brown volatile liquid which is also poisonous.
Iodine is a grey coloured solid with purple vapours.
Do the melting and boiling points of the halogens increase or decrease as you go down the group?
Increase
Note 
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