Representing Covalent Bonds
Chemistry: AQA GCSE Higher, topic 2.1.9
Representing Covalent Bonds
There are many ways of representing covalent bonds in a molecule. 4 ways of representing ammonia are shown below:
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Dot-and-cross with shells
- Dots represent the outer shell electrons of atoms of 1 element.
- Crosses represent the outer shell electrons of atoms of the other element.
- A limitation of this method is that it shows electrons differently for each atom, when they are actually exactly the same.
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Dot-and-cross without shells
- Dots represent the outer shell electrons of atoms of 1 element.
- Crosses represent the outer shell electrons of atoms of the other element.
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Ball-and-stick
- Balls represent atoms.
- Sticks represent bonds between the atoms.
- A limitation of this method is that atoms are much closer together than the diagram shows.
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Lines
- The atomic symbol represents the atom.
- Lines between the atoms represent a covalent bond.
Test yourself on Representing Covalent Bonds
What is not a way of representing covalent bonds in chemistry?
What is a limitation of the ball-and-stick diagram for ammonia?
What is the key difference between a dot-and-cross diagram with shells and one without shells?
What do the stated limitations of the dot-and-cross diagram with shells and the ball-and-stick diagram have in common?
Select the correct statement for each pair