WorksheetsCHEM: Giant Covalent Bond
Total questions: 28
Worksheet time: 17mins
Why does graphite conduct electricity?
Ions are free to move to carry the charge
Atoms can move
Free electrons that can carry the charge
Each carbon is graphite forms _____ bonds
1
2
3
4
Why is graphite so soft and slippery?
It is made of layers of atoms with weak forces between them
It is made of small molecules
It is an ionic compound
The covalent bonds are weak
Allotropes are...
different types of substances made from carbon
substances made of the same element which have different physical properties
made from elements in group 4
non-metals which conduct electricity
The diagrams show the structures of two forms, P and Q, of a solid element.
What are suitable uses of P and Q, based on their structures?
use of solid P: drilling
use of solid Q: drilling
use of solid P: drilling
use of solid Q: lubricating
use of solid P: lubricating
use of solid Q: drilling
use of solid P: lubricating
use of solid Q: lubricating
Graphite is a form of carbon.
Why can graphite be used as a lubricant?
Graphite contains delocalised electrons which move throughout the structure.
Graphite contains weak covalent bonds so the atoms move easily.
Graphite has a low melting point so it easily turns into a liquid.
Graphite has weak forces of attraction between layers so they can move.
Which substances have similar structures?
diamond and graphite
diamond and silicon(IV) oxide
graphite and poly(ethene
graphite and silicon(IV) oxide
How many silicon atoms are bonded to each oxygen atom in a crystal of silicon(IV) oxide?
1
2
3
4
Diamond is extremely hard and does not conduct electricity.
Which statement explains these properties?
It has a lattice of positive carbon ions in a ‘sea of electrons’.
It has delocalised electrons and each carbon atom forms three covalent bonds with other carbon atoms.
It has no delocalised electrons and each carbon atom forms four covalent bonds with other carbon atoms.
It has strong ionic bonds between each carbon atom.
Graphite and diamond are both forms of the element carbon.
Which option shows the number of other carbon atoms that each carbon atom is covalently bonded to in graphite and diamond?
graphite: 3
diamond: 3
graphite: 3
diamond: 4
graphite: 4
diamond: 3
graphite: 4
diamond: 4
Diamond and silicon(IV) oxide both have giant structures.
Which statements are correct?
Silicon(IV) oxide is bonded ionically.
Both substances are compounds.
There are strong covalent bonds in diamond.
Both substances have very high melting points.
Which statement describes the attractive forces between molecules (intermolecular forces)?
They are strong covalent bonds which hold molecules together.
They are strong ionic bonds which hold molecules together.
They are weak forces formed between covalently-bonded molecules.
They are weak forces which hold ions together in a lattice.
Why do weak intermolecular forces between simple molecules result in low melting and boiling points?
Little energy is needed to break the strong covalent bonds.
Little energy is needed to break the weak intermolecular forces.
Lots of energy is needed to break the weak intermolecular forces.
What bonding holds the layers together in graphite?
Ionic
Covalent
Van Der Waals
Complete the sentence:
Diamond and Graphite are both __________ of carbon
mixtures
ionic bonds
allotropes
Why does the melting point of metals increase across period 3, from Sodium (Na) to Aluminium (AI)?
Size of atoms gets smaller
Attraction force between nuclei and free electron increases
Increased space between the valence electrons in the "sea"
Increased number of valence electrons contributed to the "sea"
An alloy is made of __________ size particles while a pure metal is made up of _________ size particles.
same, different
different, same
same, same
different, different
Why are alloyed metals usually stronger?
They have atoms of different metals in them, which makes it easier for the layer to move past each other...less likely to break
They have atoms of different metals in them, which makes it harder for the layer to move past each other...less likely to break
