Bonding and Properties of Subtances Test Flashcards
Why do Atoms form chemical bonds?
To get a full outer shell and therefore become stable.
What are three different types of bonding?
Ionic, Covalent and Metallic
What type of bonding would occur between 2 metals?
Metallic
What type of bonding would occur between 2 non-metals?
Covalent
What type of bonding would occur between a non-metal and a metal?
Ionic
What is metallic bonding?
Metallic bonding is positive ions surrounded by a sea of delocalised electrons.
Why do metals conduct electricity?
Because the delocalised electrons are free to move and can therefore conduct electricity.
What is Covalent bonding?
Covalent bonding is when 2 non-metals share pairs of electrons and they are attracted to the atomic nuclei.
How does the bonding in carbon graphite and diamond differ?
Because in carbon graphite, the hexagonal sheets that make carbon graphite are separated by delocalised electrons whereas on diamond there are no delocalised electrons so it cannot conduct electricity.
What are the different shapes of simple covalent molecules?
Ask.
Why do covalent networks have high melting points?
because strong covalent bonds need to be broken, therefore requiring a lot more energy and ending up with a high melting point.
Why do covalent molecules have a low melting point?
Because the bonds aren’t as strong as those on a covalent network so therefore it requires less energy to separate them which leaves it with a low melting point.
What is ionic bonding?
Ionic bonding is the transfer of electrons from metals to non-metals to form a lattice of positively and negatively charged electrons which are held together by electrostatic attraction.
Core 15 - ?
Ask.
Why do ionic substances have high melting points?
Because the ions are held together by strong electrostatic forces therefore making them strong and requiring a lot energy to break them apart and leaving them with a high melting point.
