Bonding/structure In Elements/compounds Flashcards
What is metallic bonding
.metal atoms are held together by metallic bonding for mind a metallic crystal lattice. This is held together by the elctrostatic attraction between positive ions and delocalised electrons.
Metals conduct because the delocalised electrons are free to move from one atom to the next
Generally have melting or boiling point because of the strong electrostatic attraction between positive ions and delocalised electrons
What is covalent bonding
.covalent bonding is when atoms share Pairs of electrons. These shared pair of negative electrons are attracted to the positive nucleus of both of the atoms
What are the types of covalent compounds
.when covalent molecules met the strong covalent bonds between the atoms do not break , only the weak IMFs between molecules are broken hence why weak bp
In covalent network there is no weak IMFS just strong covalent bonds
What are the types of covalent bonds
.pure covalent bonds exist between atoms with the same elctronegafivities . This means the electrons are evenly shared between both nuclei - only LDFs exist
Polar covalent bonds exist between different electronegativies. Ie one element more attracted to he bonded electrons meaning it will pull electrons towards it
Why is ionic bonding high mp
What is ionic bonding soluble in
Have strong electrostatic attraction between ions
Tend to be soluble in polar solvents and insoluble non polar solvents
What are London dispersion forces
.they are caused by movement of electrons. As electrons move around the nucleus one side of the atom becomes more positive than the the other for fraction of a second . This then causes a temporary dipole. More electrons means stronger melt point as more LDFs
What is a permanent dipole - permanent dipole interaction
.if a molecule has polar covalent bonds then it may have a permantly negative/ positive side. Ie a permanent dipole. This means that the molecule will have DD-PD interactions. This type of IMF is stronger than LDFs
What is the definition of electronegativity
.a measure for atoms attractions for electrons in a bond
How is solubility affected by the type of bonding
.ionic lattices and other polar covalent molecules are soluble in water and polar solvents.
What is ionic character
.ionic character refers to the difference in electronegativities between atoms in a molecule
What is the bonding/structure of the noble gases
.monatomic
Weak LDFs as only bonding type
What is the bonding/structure of halogens
.diatomic
LDFS between molecules
Strong covalent bonds broken as melted
What is the bonding/structure of elements in group 6 (oxygen/sulfur)
.covalent bonds not broken when boiling only the weak LDFs
What is the bonding/structure of elements in group 5 (phosphorus/nitrogen)
.covalent molecular structure. When elements in group 5 melt/boil strong covalent bonds are not broken, only weak LDFs between molecules are broken
What is the bonding/ structure of elements in group 4 (carbon/silicon)
.covalent networks
