Characteristics Of Ionic And Covalent Compounds - Melting And Boiling Points Flashcards
Write a note on the melting and boiling points of ionic compounds.
(6)
In ionic compounds the ions can only vibrate about fixed positions
When heat is supplied, the ions gain energy and vibrate more and more
The ions vibrate so much that they break away from their fixed positions in the crystal
The crystal structure breaks down and the substance melts
The forces of attraction between the ions are so strong that most ionic substances have high melting points and high boiling points
At room temperature almost all ionic compounds are solid
How can ions vibrate in ionic compounds?
In ionic compounds the ions can only vibrate about fixed positions
What happens when heat is supplied to ionic compounds?
When heat is supplied, the ions gain energy and vibrate more and more
How do ions break away from their fixed positions in the crystal?
The ions vibrate so much that they break away
What can be observed when the crystal structure breaks down?
The substance melts
What needs to happen for an ionic compound to melt?
The crystal structure must break down
Why do ionic compounds have such high boiling and melting points?
The forces of attraction between the ions are so strong that most ionic substances have high melting points and high boiling points
What state are ionic compounds in at room temperature?
At room temperature almost all ionic compounds are solid
Write a note on the melting points and boiling points of covalent compounds.
(3)
In covalent compounds there are only weak forces between the molecules
Therefore, the melting points and boiling points are much lower
At room temperature most covalent compounds are usually either liquids or gases
Describe the forces between covalent compounds.
They are weak forced between the molecules
Describe the boiling points and melting points of covalent compounds.
Low, lower than ionic compounds
What state are covalent compounds in at room temperature?
At room temperature most covalent compounds are usually either liquids or gases
