Bonding: Ionic/Covalent/Metallic Flashcards
What is ionic bonding?
bonding resulting from electrostatic attraction between oppositely charged ions
where is the electron transferred from and to in an ionic bond?
metal to non-metal
what is the name for positively charged ion?
cation
what is the name for negatively charged ion?
anion
explain the ionic bonding in NaCl
- sodium has 11 electrons and arrangement of 1s2, 2s2, 2p6, 3s1
- chlorine has 17 electrons and arrangement of 1s2, 2s2, 2p6, 3s2, 3p5
- the 3s1 electron from sodium is transferred to the outer main level of chlorine
- sodium becomes positively charged since it has lost an electron
- chlorine becomes negatively charged since it has gained an electron
- these ions are attracted to each other and to the other oppositely charged ions by electrostatic attraction
what type of structure do ionic compounds have?
lattic structure
what state are ionic compounds at rtp?
solid
do ionic compounds have high or low mp? and why?
high mp - high amount of energy is required to break bonds in lattice
in what state do ionic compounds conduct electricity? and why?
molten - ions are free to move
why are ionic compounds brittle?
when lattice of alternating ions is displaced, the ions repel each other so break apart
what is metallic bonding?
a lattice of positively charged ions in a sea of ‘delocalised electrons’
why are metals good conductors of electricity?
delocalised electrons are free to move through structure
are metals good or bad conductors of heat?
good - high thermal conductivity (energy spread by vibration of closely packed ions and electrons moving through structure)
why do metals tend to be strong?
no individual bonds to break because of the electrons throughout the solid
how does charge affect the strength of the metal?
the greater the charge, the stronger attraction because there are more delocalised electrons so more electrostatic attraction
how does the size of a metal affect its strength?
the smaller the ion, the stronger the nuclear charge because electrons closer to nucleus
why are metals malleable and ductile?
layers of ions can easily slide over each other
why do metals have high bp and mp?
giant structure - so strong attraction between ions and electrons - therefore high amount of energy to overcome attraction
what is a covalent bond?
a shared pair of electrons
explain the covalent bonding in methane
- methane is a compound of hydrogen and carbon
- carbon has 6 electrons and an electron arrangement of 1s2 2s2 2p2
- hydrogen only has one electron - 1s1
- therefore four atoms of hydrogen are required to fill the outer main level of carbon
- four electrons from carbon and 1s1 electron from four hydrogen atoms are shared
- formula: CH4
what is another term for co-ordinate bonding ?
dative covalent bonding
what is co-ordinate bonding?
when both electrons is donated by an atom in a covalent bond
what is the term to describe the atom which accepts the electron pair?
electron-deficient
what type of electron pair is donated?
lone pair
