Chemistry A level Module 2 Exam Questions With Detailed Answers
elements - ANSWER-bonding in .................. (eg. O2, Cl2) is always non polar -
electronegativity in each molecule is the same
unequally - ANSWER-in polar bonds, the bonded electron pair is shared ....................
between bonded atoms
polar covalent bond - ANSWER-when bonded atoms are different and have
different electronegativity values it forms this
greater attraction - ANSWER-example of polar bond - hydrogen chloride, Hal
> hydrogen - electronegativity value of 2.1
> chlorine - electronegativity value of 3.0
> chlorine atom is more electronegative
> chlorine atoms has a ................... .......................... for the bonded pair of electrons
molecular dipole - ANSWER-these occur due to the unequal sharing of electrons
between atoms in a molecule.
permanent dipole - ANSWER-a small charge difference across a bond that is the
result of the electronegativities of the bonded atoms - it doesn't change
,polarisation - ANSWER-the greater the electronegativity difference between the
two atoms in a bond the greater the ...................... of the bond
covalent - ANSWER-if the electronegativity difference between atoms is 0 the
bond type is ........................
polar covalent - ANSWER-if the electronegativity difference between atoms is 0 to
1.8 the bond type is ........................
ionic - ANSWER-if the electronegativity difference between atoms is greater than
1.8 the bond type is ........................
non polar - ANSWER-covalent bonds are ......... ................
polar - ANSWER-ionic bonds are .................
opposite - ANSWER-in non-polar molecules, the bonds are arranged symmetrically
so the partial charge cancels out - the dipoles act in ..................... directions
dipoles - ANSWER-in polar molecules, the bonds are arranged asymmetrically so
the partial charges don't cancel out. The ................. act in opposite directions but
don't exactly pops each other
,intermolecular force - ANSWER-an attractive force between neighbouring
molecules
permanent dipole dipole force - ANSWER-weak attractive forces between
permanent dipoles in neighbouring polar molecules e.g. NH3, CO, CHCl3, H2O
larger - ANSWER-when a hydrogen atom bonds to a FON element, a .............. dipole
occurs than in other polar bonds
hydrogen bond - ANSWER-this is a strong dipole-dipole attraction between:
> an electron deficient hydrogen atom on one molecule
> a lone pair of electrons on a highly electronegative atoms (FON) on a different
molecule
lone pair - ANSWER-hydrogen bonding is between electron deficient hydrogen and
a ............ ............. of electrons on electronegative atom
lattice - ANSWER-in ice, hydrogen bonds hold the water molecules in a ................
structure with large, open spaces between the water molecules, held rigidly apart
volume - ANSWER-in liquid water, the hydrogen bonds collapse so the molecules
move closer to each other - take up less ..............
, less dense - ANSWER-ice is ............. .............. than liquid water because in ice the
water molecules are far apart (same mass, higher volume) but in water the
molecules are close together (same mass, smaller volume)
van der waals forces - ANSWER-attractive forces between instantaneous dipoles
and induces dipoles in neighbouring non polar molecules
increases - ANSWER-the strength of van der waals forces .................... as molecular
size and the number of electrons increases
isotope - ANSWER-atoms of the same element with different numbers of neutrons
and different masses
Avogadro's constant - ANSWER-the number of particles in each mole of carbon-12
- 6.02 x 10^23
atomic mass - ANSWER-the weighted mean mass of an element compared with
1/12th of the mass of a carbon-12 atom
mass spectrometry - ANSWER-technique used to determine the relative isotopic
mass and the relative abundance for each isotope.
elements - ANSWER-bonding in .................. (eg. O2, Cl2) is always non polar -
electronegativity in each molecule is the same
unequally - ANSWER-in polar bonds, the bonded electron pair is shared ....................
between bonded atoms
polar covalent bond - ANSWER-when bonded atoms are different and have
different electronegativity values it forms this
greater attraction - ANSWER-example of polar bond - hydrogen chloride, Hal
> hydrogen - electronegativity value of 2.1
> chlorine - electronegativity value of 3.0
> chlorine atom is more electronegative
> chlorine atoms has a ................... .......................... for the bonded pair of electrons
molecular dipole - ANSWER-these occur due to the unequal sharing of electrons
between atoms in a molecule.
permanent dipole - ANSWER-a small charge difference across a bond that is the
result of the electronegativities of the bonded atoms - it doesn't change
,polarisation - ANSWER-the greater the electronegativity difference between the
two atoms in a bond the greater the ...................... of the bond
covalent - ANSWER-if the electronegativity difference between atoms is 0 the
bond type is ........................
polar covalent - ANSWER-if the electronegativity difference between atoms is 0 to
1.8 the bond type is ........................
ionic - ANSWER-if the electronegativity difference between atoms is greater than
1.8 the bond type is ........................
non polar - ANSWER-covalent bonds are ......... ................
polar - ANSWER-ionic bonds are .................
opposite - ANSWER-in non-polar molecules, the bonds are arranged symmetrically
so the partial charge cancels out - the dipoles act in ..................... directions
dipoles - ANSWER-in polar molecules, the bonds are arranged asymmetrically so
the partial charges don't cancel out. The ................. act in opposite directions but
don't exactly pops each other
,intermolecular force - ANSWER-an attractive force between neighbouring
molecules
permanent dipole dipole force - ANSWER-weak attractive forces between
permanent dipoles in neighbouring polar molecules e.g. NH3, CO, CHCl3, H2O
larger - ANSWER-when a hydrogen atom bonds to a FON element, a .............. dipole
occurs than in other polar bonds
hydrogen bond - ANSWER-this is a strong dipole-dipole attraction between:
> an electron deficient hydrogen atom on one molecule
> a lone pair of electrons on a highly electronegative atoms (FON) on a different
molecule
lone pair - ANSWER-hydrogen bonding is between electron deficient hydrogen and
a ............ ............. of electrons on electronegative atom
lattice - ANSWER-in ice, hydrogen bonds hold the water molecules in a ................
structure with large, open spaces between the water molecules, held rigidly apart
volume - ANSWER-in liquid water, the hydrogen bonds collapse so the molecules
move closer to each other - take up less ..............
, less dense - ANSWER-ice is ............. .............. than liquid water because in ice the
water molecules are far apart (same mass, higher volume) but in water the
molecules are close together (same mass, smaller volume)
van der waals forces - ANSWER-attractive forces between instantaneous dipoles
and induces dipoles in neighbouring non polar molecules
increases - ANSWER-the strength of van der waals forces .................... as molecular
size and the number of electrons increases
isotope - ANSWER-atoms of the same element with different numbers of neutrons
and different masses
Avogadro's constant - ANSWER-the number of particles in each mole of carbon-12
- 6.02 x 10^23
atomic mass - ANSWER-the weighted mean mass of an element compared with
1/12th of the mass of a carbon-12 atom
mass spectrometry - ANSWER-technique used to determine the relative isotopic
mass and the relative abundance for each isotope.
