3: Chemical Bonding Flashcards
(35 cards)
What is atomic radius? [2]
The radius of an atom, defined as the distance from the nucleus to the outermost electrons.
What is boiling temperature?
The temperature at which a substance changes from a liquid state to a gaseous state.
What is bond angle?
The angle between two bonds that originate from the same atom.
What is bond enthalpy? [2]
The energy required to break one mole of the stated bond in a gaseous state, under standard conditions.
What is bond length?
The internuclear distance between two covalently bonded atoms.
What is a covalent bond?
The strong electrostatic attraction between two nuclei and the shared pair of electrons between them.
Polar covalent bonds occur when there is an asymmetric electron distribution within the covalent bond due to differences in electronegativities.
What is a covalent substance?
A substance that is made up of atoms that are covalently bonded to each other.
What is dative covalent bonding?
Occurs when one atom donates both electrons in a bond.
For example, in NH₄⁺, the nitrogen atom supplies both electrons for one of the covalent bonds with a hydrogen atom.
What is electronegativity?
A measure of the ability of an atom to attract a bonding pair of electrons within a covalent bond.
What is hybridisation?
The combining of two or more atomic orbitals to form new ‘hybrid’ orbitals which are different from the original orbitals.
What is hydrogen bonding?
An interaction between a hydrogen atom and an electronegative atom, commonly nitrogen, fluorine, or oxygen.
What are intermolecular forces? [2]
The forces which exist between molecules, impacting physical properties like boiling/melting point.
What is an ionic bond?
Strong electrostatic attraction between two oppositely charged ions.
What is ionic charge?
The electrical charge of an ion caused by the gain (negative charge) or loss (positive charge) of electrons.
What is an ionic compound?
A compound made up of anions and cations, held together by ionic bonds, which arise due to the electrostatic attraction between oppositely charged ions.
What is ionic radius? [2]
The radius of an ion, defined as the distance between the nucleus and the outermost electron of the ion.
What does linear mean in molecular shape?
The shape of a molecule when the central atom has 2 bonding pairs and no lone pairs of electrons.
What is melting temperature? [2]
The melting point of a substance, defined as the temperature at which it changes from solid state to liquid state.
What is metallic bonding?
Strong electrostatic attraction between positive metal ions and the sea of delocalised electrons that surround them.
What does non-linear/bent mean in molecular shape?
The shape of a molecule when the central atom has 2 bonding pairs and 2 lone pairs of electrons.
What is nuclear charge?
Total charge of all the protons in the nucleus, which increases as you go across the periodic table.
What does octahedral mean in molecular shape? [2]
The shape of a molecule with 6 bonding pairs of electrons and a bond angle of 90°.
What are permanent dipole-dipole forces?
Forces produced when molecules with polar covalent bonds interact with dipoles in other molecules.
What is a polar bond?
A covalent bond between two atoms in which the electrons in the bond are unevenly distributed.
