2 Chemical Bonding Flashcards
What is a Chemical Bond?
The linkage or force which acts between 2 or more atoms to hold them together as a stable molecule.
Molecule is formed by the combination of
2 or more atoms
The concept of chemical bond is
Chemical Bonding
Reasons for chemical bonding between atoms:
The tendency of atoms to attain stable electronic configuration of the nearest noble gas.
2 Rules of stability
Octet rule and Duplet rule
2 methods of achieving chemical bonding
- Electron transfer
2. Electron sharing
Effect on the ease of formation of ionic compound with respect to:
- IP
- EA
- EN
- Inversely -> Cation
- Direct (Note: EA is only represented by -ve sign-> here absolute value is taken). -> Anion
- EN difference should be large.
Effect on the ease of formation of Covalent compound with respect to:
- IP
- EA
- EN
All the values should be high.
EN difference should be negligible.
Ionic Bond formation is due to _____.
Electrostatic force of electrostatic force of attraction between the ions.
Electrovalency
Number of electrons donated or accepted by the valence shell of an atom of an element.
____ may or may not exist independently. But ______ exist independently in solution.
Atoms; Ions;
In oxidation, there is
_____ in electrons or
____ in hydrogen or
______ in oxygen
Lose; Lose; Gain;
In reduction, there is
_____ in electrons or
____ in hydrogen or
______ in oxygen
Gain; Gain; Lose;
Ionic equation should have
Reduction and Oxidation equations
Electrovalent compounds involves ______ and ______. Covalent compounds involve _____ and _______.
Metal and Non-Metal.
Non-Metal and Non-Metal.
Number of bonds of each type is based on
the valency of the atoms
Covalent compound
Chemical bond formed due to the mutual sharing of electrons.
Between non-metallic elements
Covalency
Number of electron pairs which an atom shares with one or more atom of the same or different kind to achieve stable electronic configuration.
Non polar
- Shared pair of electrons are equally distributed between the 2 atoms.
- No charge seperation.
- Electrically neutral
Which type of bond has absolute symmetry?
Non-Polar covalent bonds
Polar
- Shared pair of electrons are unequally distributed between the 2 atoms.
- Charge seperation takes plalce.
- High electronegative -> slight negative charge.
If out of 2 atoms, one atom contributes x electrons. Then the bond is ____.
x covalent bond.
____ electrons in the outershell of each nitrogen atom are not involved in sharing during the formation of N2 molecules.
2
CCl4 has ____ single covalent bonds.
4
Is methane non-polar?
Yes
Does nitrogen molecule have a lone pair?
Yes. 1.
Does Methane molecule have a lone pair?
No
Number of lone pairs in O2
2.
Despite the C-Cl bond being polar, why not CCL4 not polar?
Due to symmetry, they canel out each other.
What is lone pair of electrons?
Pair of electrons not shared with any other atom.
An example of a stable positive ion?
Hydronium Ion.
Number of lone pairs in hydronium ion?
1
Addition of ___- to water results in the release of H ion.
Acids
Number of lone pairs in ammonium ion?
0
What is a coordinate bond?
- Type of covalency
- one of the combining atoms contribute both of the shared electrons.
- Bond; shared pair; both electrons from the same atom.
Co-Ordinate bond doesnt come under covalency.
True or False.
False.
Which bond has properties of both ionic and covalent?
Co-ordinate
Another names for co-ordinate bonds
dative or co-ionic bond.
Co-ordinate bond is also called co-coordinate bond.
True or false.
False.
A compound which has Electrovalent and Covalent compound:
NaOH
A compound which has Covalent and Co-ordinate compound:
CO and HNO3
HNO3 has
A covalent and co-ordinate bond
Compounds that has Ionic, Covalent and Co-ordinate bond
(NH4)Cl and K4 [Fe(CN)6]
Ionic and Covalent compounds, exists in and why?
Crystalline hard solids -> Strong force of attraction between the ions, Gas, Liquids or Soft solids -> Weak force of attraction.
Ionic and Covalent compounds, force of attraction:
Strong, Weak
What forces are there between the ions/molecules in ionic and covalent compounda?
Electrostatic forces -> Between ions, Vander waal’s forces -> Between molecules
Covalent compounds are gas if ______ and liquids or soft solids if _______.
Molecules are less; Molecules are more;
Ionic and Covalent compounds, Volatility
Non-Volatile, Volatile
Ionic and Covalent compounds, MP and BP. Reason.
HIGH -> Strong Electrostatic force of attraction between ions this large amount of energy to break the bond,
LOW -> Weak vaner waals force -> Less amount of energy.
Ionic and Covalent compounds, Conduction of heat
Good
Bad
Ionic compounds, Conduction of electricity
Solid state -> Non-Conductors
Liquid state -> Good conductors
Strong ES force keeps them in position. Weakened in molten and disappears in solution.
The strong force of attraction _____ in molten state and _____ in solution state.
Weakened; Disappears;
Covalent compounds, Conduction of electricity
Any state -> Non-conductors;
Only contains molecules and not ions. -> non-polar
Show charge seperation and seperate and dissosciate in H2O -> polar
Ionic and Covalent compounds, Electrolysis
Ionic -> Yes. IN (liquid) or (aq) state.
Covalent -> No. But polar undergoes in (aq) state.
Ionic and Covalent compounds, Solubility
Ionic -> Water;
Covalent -> Organic solvents; (non-polar);
Organic solvents are always _______. (type)
Non-Polar.
Ionic and Covalent compounds, Insolublity
Ionic -> Organic solvent
Covalent -> Water;
What is Di-electric constant?
Capacity to weaken the force of attraction, resulting in free ions.
Capacity to weaken the force of attraction, resulting in free ions.
Di-electric constant
“LIKE DISSOLVES LIKE”
True or False.
TRUE!!!
Water has a _____ di-electric constant. Organic solvents have a ____ di-electric constant.
High, Low.
Reason for the solubility of non-polar compounds in organic compounds is
“Like Dissolves Like”
Ionic and Covalent compounds, Reaction
Ionic -> High Speed IONIC Reactions. Rapidly regroup.
Covalent -> Slow speed molecular reactions. -> Slowly established.
Ionic and Covalent compounds, Methods of charge creation
Ionic -> Electrolytic dissociation
Covalent -> Ionization.
on passage of current.
Seperation of ions is called ____.
Formation of ions is called _________.
Electrolytic dissociation;
Ionization.
Ionization happens in _____- state. Electrolytic dissociation happens in _____- state.
Solution state; Molten state;
Electrolytic dissociation and Ionization occurs while there is a
Passage of electric current.
