Alkali metals react with non-metals to form __________.
Noble gases
Acids
Macromolecules
Hydroxides
Ionic compounds
Insoluble Bases
Hydrogen
Ionic compounds are held together by ___________.
Strong ionic bonds
Strong intermolecular forces
Very strong Covalent Bonds
Delocalised electrons
Strong Electrostatic forces
Ionic bonds dissolve in water.
When atoms share electrons they form __________.
Ionic bonds
Covalent bonds
Electrostatic forces
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.
Microscope
Oscilloscope
Set of accurate scales
Mass spectrometer
Soluble salts can be made from:
Halogens
Metals
Insoluble bases
Oxygen
Alkalis
Water
Insoluble salts can be made by mixing appropriate solutions of _______ so that a(n) __________ is formed.
Acid(s)
Bases(s)
Hydroxide(s)
Alkali(s)
Precipitate
Gas
Ions
sodium hydroxide
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 _________.
Gain
Lose
Create
Neutralisation
Oxidation
Reduction
At the positive electrode, _________ charged ions _______ electrons, this is known as _________.
Negatively
Positively
Neither decrease nor increase electrons
Oxidisation
In electrolysis the positive electrode is usually made of ____________
Francium
Steel
Copper
Boron
Iron
Carbon
Charcoal
Plastic
Wood
