Chemistry Concept Maps Class IX • Matter in Our Surroundings • Is matter around us pure • Atoms and Molecules • Structure of Atom
Class-IX(Chemistry) (e.g. NaCl = 58.5 g)
6.023 × 10 Atoms
6.023 × 1023 Ions
23
(e.g. oxygen gas = 32 g)
GAM Gram formula mass
GMM
In terms of mass
In terms of particles
6.023 × 1023 Molecules
(e.g. oxygen atom = 16 g)
Volume N = NA Molar volume
(No. of atoms in a molecule)
n=
Mass N = GAM/GMM NA
Mass GAM/GMM
Atomicity Chemical formulae
Molecule of element
In terms of volume
Volume Mass = GAM/GMM Molar volume
Some useful formulae
Mole
(Mass of one molecule)
Molecular mass
Molecule
Atomic mass
22.42
(Mass of one atom)
Molecule of compound (Positively charged +
ion e.g. K , Ca
2+
)
Atom exist as
Cation Electopositive radicals
Electronegative radicals
ATOM
Valency of ion
Ion
Polyatomic ion
Anion (Negatively charged –
2–
ion e.g. F , O
)
Ionic compound
Formula unit
Formula mass (Mass of one formula unit)
(Mass of 1 mole molecules)
(Mass of 1 mole atoms)
(Short hand representation)
Symbol
(Present two or more atoms e.g. OH–, SO42– )
Dalton's symbols Rules for writing formulae
Formation
GAM
(Present one atom only e.g. H+, Na+ )
(Charged species)
GMM
N NA
Molar mass (Mass of 1 mole)
(Smallest particle of matter)
Monoatomic ion
n=
Modern symbols
Significance
Rules for writing symbols
• Represents name of element • Represents no. of atoms
Class-IX(Chemistry)
MAP-1
Phosphorus
Iron
Volatility
Non-Metals
Solubility
Boiling point
Metals
Metalloids (Intermediate properties of metals & non-metals)
Solid
Based on principle
Melting point
Sublimation
Radioactive
Liquid
Large proportion
Small proportion
(e.g. Water in sugar solution)
(e.g. Sugar in sugar solution)
Classification
Diffusion
Density
(Intermixing of particles on their own)
Gas
Solvent
Solute
Normal
Separation Element
(Water)
Components
Pure substance (only one kind of particles present)
(Matter that can't be broken into simpler ones.)
True solution
Homogeneous
Mixture
SUBSTANCE
–7
(Particle size < 10 cm)
(More than one kind of particles present e.g. soil, air)
Concentration
Compound
Suspension
Heterogeneous
(Consists of 2 or more elements combined chemically
–5
(Particle size > 10 cm) Percentage method
Lime Water
Organic
Classification
Inorganic (Obtained from rocks and minerals e.g. salt, marble)
Colloidal solution –7
–5
(Liquid or solid in (Particle size between 10 – 10 cm) (Solid in solid e.g. milky glass) gas e.g. fog, smoke) (Obtained from living beings Aerosol e.g. alcohol, sugar) Salt (Gas in liquid Foam e.g. shaving cream) (Formed by acid & base
Acid (Turns blue litmus red e.g. HCl, H2SO4)
Tyndall Effect
Base
e.g. NaCl, CaCO3)
(Turns red litmus blue e.g. NaOH, KOH)
(Liquid in liquid e.g. milk)
Classification
Solid sol Gel Solid foam
Emulsion Sol (Solid in liquid e.g. blood)
(Gas in solid e.g. Pumice)
(Liquid in solid e.g. butter)
Mass % of solute m solute M solution
× 100
Volume% of solute v solute × 100 V solution
Class-IX(Chemistry)
MAP-2
Water
Alcohol
Solvent MgO
Al2O3
Adsorbent medium
Principle (Ability to sublime) Example (Sand & I2)
Method
Principle (Density)
Filter paper
Principle (Relative solubility & affinity of constituents)
Principle (Solubility)
Sublimation
Centrifugation
Chromatography
Principle (Density)
Example (Components of ink)
SEPARATION TECHNIQUES
Using Suitable Solvent Example (Sugar/Sand) Principle (Boiling point)
Example (separation of cream from milk)
Separating funnel
Fractional distillation
Evaporation Distillation Example (Coloured components of blue ink solution)
Principle (Boiling point)
Principle (Boiling point)
Example (Oil & Water)
Example (Alcohol & water)
Class-IX(Chemistry)
MAP-3 Liquid N2 boils off followed by liquid O2
Heavy impurities settle down
Suspended impurities separates Rusting
Fractional distillation
Combustion
Sedimentation Filtration Example
SEPARATION OF GASES FROM AIR
CHANGES IN MATTER
CITY WATER SUPPLY
Chemical change
Definition
Purification
Liquefaction
Physical change
Sterilization
(Change in chemical Characteristics properties) • New product formed • Permanent and irreversible change • Energy absorbed or evolved
(At high P & low T) Example
Definition (Change in physical Characteristics properties) Removal of dust, gases & water vapour
Removal of harmful micro organism
• No new product formed • Temporary and reversible change • No net gain or loss of energy
Condensation
Class-IX(Chemistry)
Freezing
Melting point
Freezing point
Condensation point
Boiling point Condensation
Latent heat Melting
n
Solid to liquid & vice versa
n
Humidity
Surface area Temperature
Wind speed
n
Liquid to gas & vice versa
Boiling (Heat energy required to change 1 kg of liquid into gas at Latent heat atmospheric pressure and its B.P.)
By altering temperature
1 Humidity
n
(Heat energy required to change 1 kg of solid into liquid at atmospheric pressure and its M.P.)
Solid to gas & vice versa
W.S.
Sublimation
(Zig-zag motion)
Brownian motion
Camphor
Nature of substance
By altering pressure
Interconversions
Liquefaction (At high P & low T)
Factors affecting
Dissolving solid in liquid
Movement of pollen grains
Evidence
Evaporation
Physical nature
MATTER
Matter consists of particles
(Anything that has mass, occupies space.) Difference between boiling and evaporation
Evaporation It is a surface phenomenon. It occurs at all temperatures below B.P.
Uses of cotton clothes
Boiling
Characteristics
Classification
Solid
It is a bulk phenomenon.
BEC
It occurs at B.P. only.
The rate of evaporation The rate of boiling does depends upon the surface not depend upon the area of the liquid, humidity surface area, wind speed, temperature & wind speed and humidity.
Plasma
Liquid
Small particle size Interparticle spaces
Cohesive force (between similar atoms)
Interparticle attraction
Particles moving constantly
Gas Diffusion
(between dissimilar atoms) Adhesive force
Class-IX(Chemistry)
( In cancer, thyroid etc.)
Medicine
(Cracks in metal casting)
(to find the age of fossil)
Carbon dating
Reaction (e.g. esterification reaction) mechanism
Industry
(No. of protons) (Sum of protons & neutrons)
Mass number
(e.g. Cl = 35.5u, Cu = 63.5 u)
Application
(Traces used Agriculture for plant nutrition)
Fractional atomic mass (Diff. physical properties same chemical properties)
(Diff. Z, same A)
Atomic number
Isotope
Isobar
Characteristics
(Same Z, diff. A)
Octet rule Isotone
Valency
Isoelectronic
(Same no. neutrons in different atoms)
(Combining capacity of an atom)
(Diff. atoms, ions molecules with same no. of electrons)
Electron
Proton
Discovery J.J. Thomson
E. Goldstein
James Chadwick
e
p
n
Nature
Negatively charged
Positively charged
Neutral
Relative charge
-1
+1
0
Relative mass Absolute mass
1.602 × 10
-19
C 1.602 × 10
1 1837
9.109 × 10
-19
C
1 -28
g
1.6725 × 10
(Contains protons & neutrons)
Neutron
Symbol
Absolute charge
Electronic configuration (Distribution of electrons in shells)
Electron Property
(8 electrons in outermost shell)
Fundamental particles
Proton
0
Neutron
-24
g 1.6748 × 10
-24
ATOM
Main features (Atom is electrically neutral)
(Electrons revolve)
Bohr's model
g
Rutherford model
Postulates
(K, L, M, N)
Defects (Facts of Rutherford experiment)
• Most a -particles Observation passed straight. • Some deflected through large angles • Some retraced their path
Defects Alpha particle scattering experiment
a -particles
Nucleus
Extranuclear region
(Smallest particle of matter)
Thomson model
1
Atomic structure
Shell
• Electrons revolve in shells • Fixed energy of each orbit • Energy increases from K to N • No gain or loss of energy in shell • Electron jumps to higher or lower orbit by gain or loss of energy.
Orbital Conclusion •Large empty space • Nucleus inside atom • Very small nucleus as compared to atom
Subshell (s, p, d, f)
