What happens when sodium reacts with chlorine to form sodium chloride?
Electrons transfer from sodium atoms to chlorine atoms
Electrons transfer from chlorine atoms to sodium atoms
Sodium atoms share pairs of electrons with chlorine atoms
What type of structure is present in solid potassium chloride?
Giant covalent structure
Giant ionic lattice
Individual pairs of ions
What is an ionic bond?
A strong force of attraction between positive ions
A strong force of attraction between negative ions
A strong force of attraction between oppositely charged ion
How is a covalent bond formed?
By sharing a pair of electrons between two atoms
By transferring electrons to form oppositely charged ions
By delocalised outer electrons in a lattice of positive ions
What type of elements usually form covalent bonds?
Metals
Metals and non-metals
Non-metals
Phosphorus is in group 5 (IUPAC group 15). How many covalent bonds does phosphorus usually form?
3
5
1
Which of the following exists as a giant covalent structure?
Carbon dioxide
Magnesium oxide
Silicon dioxide
Approximately how many carbon atoms might be joined together in a polymer molecule?
Five
Fifty
Five thousand
What kind of bonding is present in iron?
Metallic
Ionic
Covalent
What happens to the outer electrons in metallic structures?
They are shared in pairs between atoms
They are transferred between atoms to form positive and negative ions
They form a 'sea' of delocalised electrons