Alkali metals react with non-metals to form __________.
Ionic compounds are held together by ___________.
Strong ionic bonds
Strong intermolecular forces
Very strong Covalent Bonds
Strong Electrostatic forces
Ionic bonds dissolve in water.
When atoms share electrons they form __________.
Simple molecules do not conduct electricity because . . . .
They have delocalised electrons.
The intermolecular forces are too weak.
The molecules have no overall charge.
There are no layers.
They are too large.
When melted ionic compounds conduct electricity.
What function of Nitinol makes it particularly useful in braces.
It is a shape memory alloy.
It is not broken down by saliva.
It can be controlled by remote as to where the teeth move.
It is very hard so the teeth cannot move.
Not really a proper question just useful info in the explanation. RAM stand for Relative Molecular mass
Gas chromatography uses ________, to help identify the substance.
The speed of the substance in column
The time taken to travel through the column
The size of the substance
The mass of the substance
The number of substances
The gas chromatography column can be linked to a(n) __________, to identify the substances leaving the column.
Set of accurate scales
Soluble salts can be made from:
Insoluble salts can be made by mixing appropriate solutions of _______ so that a(n) __________ is formed.
Alkalis: (tick the correct statements)
Have a pH lower than 7
Turn UI green, blue and red.
Are also known as insoluble bases
Are also known as soluble hydroxides
Are also known as insoluble hydroxides
Can come in the form metal oxides
At the negative electrode, positively charged ions ________ electrons, this is known as _________.
At the positive electrode, _________ charged ions _______ electrons, this is known as _________.
Neither decrease nor increase electrons
In electrolysis the positive electrode is usually made of ____________