c3. structure and bonding Flashcards
What are three types of chemical bonds?
Ionic, covalent and metallic bonds
What is an ionic bond?
A bond between a metal and nonmetal in which electrons has been exchanged
What is a covalent bond?
A bond between two nonmetals in which electrons are shared
What is a metallic bond?
A bond between metal atoms in which electrons are delocalised
How does an ionic compound form?
The metal loses electrons to get a full outer shell becoming a positively charged ion while the non-metal gains electrons becoming a negatively charged ion. The opposite charge ions are electrostatically attracted to each other.
What is the charge of an ion from group one
+1
What is the charge of an ion from group 2?
+2
What is the charge of an ion from group 6?
-2
What is a charge of an ion from group 7?
-2
What is the charge of an ion from group 7?
-1
What is an ionic compound?
A giant structure of ions which are held together by a strong electrostatic forces of attraction between oppositely charged ions.
What is the state symbol for a solid?
(s)
What is the state symbol for a liquid?
(l)
What is the state symbol for a gas?
(g)
What is the state symbol for a solution?
(aq)
What are the properties of ionic compounds?
High melting and boiling point don’t conduct electricity when solid but due when molten or dissolved
Why do ionic compounds have high melting and boiling points?
Strong bonds between molecules which takes lots of energy to overcome
Why can’t ionic compounds conduct electricity when solid?
Ions are unable to move freely
Why can ionic compounds conduct electricity when molten or dissolved?
Ions are free so able to move freely
What are the properties of simple molecules?
Low melting and boiling point poor conductors
Why do simple molecules have low melting and boiling points?
Weak bonds between the molecules and so little energy is needed to overcome these bonds
What are example of giant covalent structures?
Diamond and graphite
What is the structure of diamond?
Each carbon atom is convolently bonded to 4 others in giant structures
What is the structure of graphite
Each carbon atom is covalently bonded to 3 others in giant structure
Why can graphite conduct electricity?
It has three electrons to move
Why do diamond and graphite have high melting and boiling points?
Strong covalent bonds between atoms which take lots of energy to overcome
What is graphene?
A single layer of graphite
What are the properties of graphene?
Conducts electricity and strong
What are fullerenes?
Molecules of carbon atoms with hollow shapes
