Topics
Matter in Our Surroundings
- Matter
- Characteristics of Molecules of Matter
- The Solid State
- The Liquid State
- The Gaseous State
- Plasma
- Bose-einstein Condensate
- Change of State of Matter
- Concept of Melting (Fusion)
- Concept of Boiling (Vaporization)
- Concept of Sublimation
- Concept of Freezing (Solidification)
- Concept of Condensation (Liquefaction)
- Concept of Desublimation (Deposition)
- Concept of Evaporation
Is Matter Around Us Pure
- Matter
- Concept of Mixture
- Concept of Solution
- Concentration of a Solution
- Concept of Suspension
- Concept of Colloidal Solution
- Evaporation Method
- Centrifugation Method
- Using a Separating Funnel Method
- Sublimation Method
- Chromatography Method
- Distillation Method
- Fractional Distillation Method
- Crystallisation Method
- Concept of Physical Changes
- Types of Pure Substances
- Concept of Elements
- Concept of Compounds
Atoms and Molecules
- Introduction of Atoms and Molecules
- Law of Conservation of Mass
- Law of Constant Proportions
- Concept of Atom
- The Modern Day Symbols of Atoms of Different Elements
- Concept of Atomic Mass
- Concept of Molecule
- Molecules of Elements
- Molecules of Compounds
- Concept of an Ion
- Writing Chemical Formulae
- Concept of Molecular Mass
- Concept of Molecular Mass
- Mole Concept
- Atoms and Molecules Numericals
Structure of the Atom
- Concept of Atom
- Charged Particles in Matter
- The Structure of an Atom
- J. J. Thomson’s Model of an Atom
- Rutherford’s Model of an Atom
- Neil Bohr’s Model of Atom
- Concept of Proton
- Concept of Neutrons
- Concept of Electron
- Concept of Electrons Distributed in Different Orbits (Shells)
- Concept of Valency
- Concept of Atomic Number
- Concept of Mass Number
- Concept of Isotopes
- Concept of Isobars
- Structure of Atom Numericals
The Fundamental Unit of Life
- The Invention of the Microscope and the Discovery of Cell
- Prokaryotic and Eukaryotic Cell
- Osmosis and Osmotic Pressure
- Structure of a Cell
- Plasma Membrane Or Cell Membrane
- Cell Wall
- Nucleus
- Cytoplasm
- Endoplasmic Reticulum (Er)
- Golgi Apparatus
- Lysosomes
- Mitochondria
- Plastids
- Vacuoles
- Difference Between Plant Cell and Animal Cell
- Cell Inclusion
Tissues
Diversity in Living Organisms
Motion
- Concept of Motion
- Displacement
- Concept of Motion
- Motion Along a Straight Line
- Uniform Motion and Non-uniform Motion
- Measuring the Rate of Motion - Speed with Direction
- Rate of Change of Velocity
- Graphical Representation of Motion: Distance - Time Graphs
- Graphical Representation of Motion: Distance - Time Graphs
- Graphical Representation of Motion: Velocity - Time Graphs
- Equations of Motion by Graphical Method
- Derivation of Velocity - Time Relation by Graphical Method
- Derivation of Position - Time Relation by Graphical Method
- Derivation of Position - Velocity Relation by Graphical Method
- Uniform Circular Motion
- Motion (Numerical)
Force and Laws of Motion
- Force
- Force - Push Or Pull
- Forces Are Due to an Interaction
- Exploring Forces
- Force Can Change the State of Motion
- Force Can Change the Shape of an Object
- Concept of Contact Forces
- Concept of Non-contact Forces
- Balanced and Unbalanced Forces
- Newton's First Law of Motion
- Inertia and Mass
- Newton's Second Law of Motion
- Newton's Third Law of Motion
- Conservation of Momentum
- Force and Laws of Motion (Numerical)
Gravitation
- Concept of Gravitation
- Newton’s Universal Law of Gravitation
- Free Fall
- To Calculate the Value of G
- Motion of Objects Under the Influence of Gravitational Force of the Earth
- Concept of Mass
- Concept of Weight
- Pressure
- Buoyancy Force
- Pressure Exerted by Liquids and Gases
- Density of the Fluid
- Archimedes' Principle
- Relative Density
Work and Energy
- Work
- Work Done by a Constant Force
- Energy
- Different Forms of Energy
- Kinetic Energy
- Potential Energy
- The Potential Energy of an Object at a Height
- Work Done by a Energy
- Work Done by a Power
- Conversion of Energy from One Form to Another
- Law of Conservation of Energy
- Rate of Doing Work
- Energy
- Work and Energy (Numericals)
Sound
- Sound
- Production of Sound
- Propagation of Sound
- Sound Need a Medium to Travel
- Longitudinal Nature of Sound Waves
- Characteristics of a Sound Wave
- Speed of Sound
- Reflection of Sound
- Reflection of Sound – Echo
- Reflection of Sound – Reverberation
- Reflection of Sound
- Range of Hearing in Humans
- SONAR
- Structure of the Human Ear (Auditory Aspect Only)
- Sound (Numerical)
Why Do We Fall ill
- Health and Its Failure
- The Significance of ‘Health'
- Personal and Community Issues Both Matter for Health
- Distinctions Between ‘Healthy’ and ‘Disease-free’
- Identification of Disease
- Categories of Diseases
- Chronic Diseases and Poor Health
- Causes of Disease
- Infectious and Non-infectious Causes
- Categories of Diseases
- Infectious Agents
- Diseases Caused by Bacteria
- Diseases Caused by Parasitic Worms: Taeniasis
- Diseases Caused by Protozoa
- Modes of Transmission of Diseases (Air, Water, Food, Insects)
- Organ-specific and Tissue-specific Manifestations of Disease
- Principles of Prevention of Diseases
- Principles of Treatment of Diseases
Our Environment
- Introduction of Our Environment
- The Breath of Life - Air
- The Role of the Atmosphere in Climate Control
- Movements of Air (Winds) and Its Role in Bringing Rains Across India
- Water - A Wonder Liquid
- Concept of Water Pollution
- Mineral Riches in the Soil
- Biogeochemical Cycle
- The Water-cycle
- The Nitrogen-cycle
- The Carbon Cycle
- The Oxygen-cycle
- Ozone Layer Depletion
Improvement in Food Resources
notes
Factors affecting the rate of evaporation:
- Surface area: The rate of evaporation increases on increasing the surface area of the liquid.
- Temperature: The rate of evaporation increases with an increase in temperature.
- Humidity: Decrease in the humidity increases the rate of evaporation.
- Wind speed: An increase in the wind speed increases the rate of evaporation.
Evaporation causes cooling:
During the process of evaporation, the particles of liquid absorb energy or latent heat of vaporisation from the surrounding to get converted to gaseous state. This absorption of energy from the surroundings make the surroundings cold.
For example: The perspiration or sweating in our body keep the body temperature constant by taking away the extra heat from body as the latent heat of vaporisation.
What happens when you pour some acetone (nail polish remover) on your palm? The particles gain energy from your palm or surroundings and evaporate causing the palm to feel cool. After a hot sunny day, people sprinkle water on the roof or open ground because the large latent heat of vaporisation of water helps to cool the hot surface. Can you cite some more examples from daily life where we can feel the effect of cooling due to evaporation?
Why should we wear cotton clothes in summer?
During summer, we sweat more because of the mechanism of our body which keeps us cool. We know that during evaporation, the particles at the surface of the liquid gain energy from the surroundings or body surface and change into vapour. The heat energy equal to the latent heat of vaporisation is absorbed from the body leaving the body cool. Cotton, being a good absorber of water helps in absorbing the sweat and exposing it to the atmosphere for easy evaporation.
Why do we see water droplets on the outer surface of a glass containing ice-cold water? Let us take some ice-cold water in a tumbler. Soon we will see water droplets on the outer surface of the tumbler. The water vapour present in air, on coming in contact with the cold glass of water, loses energy and gets converted to liquid state, which we see as water droplets
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- Evaporation
- Rate of Evaporation
- Factors Affecting Evaporation
- How Does Evaporation Cause Cooling?
