Types Of Substances Flashcards
What are ionic compounds made up of?
A metal and a nonmetal
Describe the structure of ionic compounds.
Regular structures (giant ionic lattices) with strong electrostatic forces of attraction between oppositely charged ions
What are the melting and boiling points of ionic compounds like?
High melting and boiling points due to strong bonds
Why do ionic compounds conduct electricity when melted or dissolved in water?
Ions are free to move and carry current
Do ionic compounds conduct electricity as solids?
No, because ions are fixed and cannot move
What happens to ionic compounds when they are dissolved in water?
They often dissolve to form an aqueous solution
What are simple molecular compounds usually made up of?
Nonmetal elements
What is the state of substances that consist of small molecules?
Usually gases or liquids with low boiling and melting points
What type of forces are present in small molecular compounds?
Weak intermolecular forces
What must be broken to boil or melt small molecular compounds?
Intermolecular forces, not covalent bonds
How do the melting and boiling points of small molecular compounds change with molecule size?
Larger molecules have higher melting and boiling points
Do small molecular compounds conduct electricity?
No, because they do not have an overall electric charge
What can happen to some small molecular compounds in water?
They can break down to form ions that conduct electricity
Are small molecular compounds generally soluble in water?
Many are insoluble, but some are soluble due to stronger intermolecular forces with water
What elements make up giant covalent structures?
Nonmetal elements
What is the melting point of substances with giant covalent structures?
Very high melting points
What type of bonds link atoms in giant covalent structures?
Strong covalent bonds
What must happen to the strong covalent bonds in giant covalent structures to melt or boil them?
They must be overcome
Can some giant covalent structures conduct electricity?
Yes, but others cannot
