"Unlock Success with Comprehensive Study Notes!
Are you tired of sifting through endless textbooks and lecture notes? Do you wish you had a reliable resource to help you ace your exams and assignments? Look no further! I'm offering meticulously crafted study notes that cover the key concepts, insi...
Introduction
Atoms are generally not capable of free Definition
existence but groups of atoms of the same or
The forces of attraction which
different elements exist as one species, e.g., H2, holds the atoms together
O2, P4. within a molecule is called
Most of the molecules are cluster of atom. Chemical Bond.
Molecule will only be formed if it has lower energy
and is more stable, than the individual atoms.
Chemical Bond
Concept Ladder
y A force when acts between two or more
atoms to hold them together as a stable Attraction ∝ 1/energy
molecule, the bond thus formed is chemical ∝ Stability
bond.
y It is group of two or more atoms involving
redistribution of electrons among them.
y This process accompanied by decrease in
energy. Rack your Brain
y Decrease in energy ∝ Strength of the bond.
y Therefore molecules are more stable than How do atoms combined to form
atoms. molecules?
Ex. Cl2, HCl, NaCl etc.
Cause of Chemical Combination
(1) Tendency to acquire minimum energy
(a) When two atoms comes closer, nucleus
of one atom attracts the electron of
Concept Ladder
another atom.
(b) When net result is attraction, the Inert gas elements do not
total energy of the system (molecule) participate in the bond
decreases and chemical bond forms. formation because they
have stable electronic
(c) Bond formation is an exothermic
configuration and have
Chemical Bonding
process. minimum energy.
1.
, (2) Tendency of acquire noble gas configuration
(a) Atom combines to acquire noble gas
configuration. Rack your Brain
(b) (b) In formation of bond only outermost
Why inert gases are generally
electron i.e. ns, np and (n–1)d electrons
unreactive?
participate.
How atom combine to form molecule.
(i) To obtain stable octet configuration or inert
gas configuration.
(ii) Decrease in Potential Energy — When two
atoms approaches to each other then there Rack your Brain
is force of repulsion due to nucleus of two
atoms & also force of attraction between Why do atoms form bonds?
nucleus of one atom & electron of another
atoms.
Chemical Bonding
2.
,y At point (b) force of attraction is dominating
so PE decreases & when PE becomes min.
then bond is formed. When atom is made Concept Ladder
more closer, repulsion increases. Hence,
Energy is absorbed to
after point (b) PE increases. break bonds. Energy is
y During molecule formation attraction > relased when new bonds
repulsion PE decreases. form. Bond making is an
y ⚫ Between two atoms, when at any exothermic process.
particular distance the PE is minimum or
when they combine then the distance or
length between them is termed as bond
length.
Note :
y The time at which molecule is formed, there
is decrease in potential energy.
y For graph N2 molecule is more stable than
O2.
Chemical Bonding
3.
, y He2 molecule has no graph on PE-axis, as
they exist in the form of atom only not in
molecule. So for all inert gases there is no Concept Ladder
graph on PE-axis.
y Between two atoms, when at any particular Lewis octet rule is acquire
inert gas configuration
distance the PE is minimum or when they
atoms loose or gain
combine with each other. electron or share electron.
Lewis symbol
To represent the Lewis symbol of a particular
element valence electron is represented as a
dot. Some examples of Lewis symbol of various
elements are given in the table.
LEWIS SYMBOL OR ELECTRON DOT SYMBOLS
Element Electronic Configuration Lewis Symbol
•
Hydrogen 1 H
Helium (He) 2
He
Lithium (Li) 2, 1
Li
Carbon (C) 2, 4 ⋅ C ⋅
Nitrogen (N) 2, 5 : N ⋅
Chemical Bonding
4.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller zsstudynotes. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $6.49. You're not tied to anything after your purchase.
