Grade 8
  1. Introduction to Chemistry  1.1. Nature and scope of chemistry  1.2. Importance of chemistry in daily life  1.3. Chemistry and its relation with other sciences  1.4. The role of chemistry in industry, medicine and the environment  1.5. Scientific investigation and experimental methods in chemistry
  2. Matter and its properties  2.1. Definition and classification of matter  2.2. Physical and chemical properties of matter  2.3. Law of conservation of matter  2.4. Extensive and Intensive Properties of Matter  2.5. Kinetic molecular theory of matter  2.6. States of matter: solids, liquids, gases, plasmas, and Bose-Einstein condensates  2.7. Changes in state and energy are involved  2.8. Diffusion and Brownian motion
  3. Elements, Compounds, and Mixtures  3.1. Definition and differences between elements, compounds, and mixtures  3.2. Atomic Structure and Atomic Number  3.3. Chemical symbols and formulas  3.4. Trends in the Periodic Table (Groups and Periods)  3.5. Classification of Elements: Metals, Nonmetals and Metalloids  3.6. Rare Earth Elements and Transition Metals  3.7. Types of mixtures: homogeneous and heterogeneous  3.8. Separation of Mixtures Using Physical and Chemical Methods
  4. Separation Techniques  4.1. Filtration, Sedimentation and Decantation  4.2. Evaporation and crystallization  4.3. Distillation and Fractional Distillation  4.4. Chromatography and its applications  4.5. Sublimation in the purification of compounds  4.6. The role of centrifugation in biochemical processes
  5. Atomic Structure  5.1. Dalton's atomic theory  5.2. Structure of the atom: protons, neutrons and electrons  5.3. Bohr's atomic model  5.4. Introduction to Quantum Mechanical Model  5.5. Electron Configuration and Energy Levels  5.6. Excitation and emission spectra  5.7. Isotopes and their applications
  6. Periodic Table and Chemical Trends  6.1. History and Development of the Periodic Table  6.2. Modern periodic law  6.3. Periodicity and trends in atomic and ionic sizes  6.4. Ionization Energy, Electron Affinity and Electronegativity  6.5. Introduction to Lanthanides and Actinides  6.6. Application of periodic trends in chemistry
  7. Chemical Bonding and Molecular Structure  7.1. Types of chemical bonds: ionic, covalent and metallic bonds  7.3. Polar and Nonpolar Molecules  7.4. Hydrogen bonding and its applications  7.5. Intermolecular forces: dipole-dipole, London dispersion force
  8. Chemical Reactions and Stoichiometry  8.1. Chemical Equations and Balance  8.2. Types of Chemical Reactions: Combination, Decomposition, Displacement and Redox  8.3. Introduction to stoichiometry and the mole concept  8.4. Limiting reactant in chemical equations  8.5. Reaction rate, catalyst, and factors affecting reaction rate
  9. Acids, Bases and Salts  9.1. Definition and Properties of Acids and Bases  9.2. Strong vs. Weak Acids and Bases  9.3. pH Scale and pH Calculation  9.4. Neutralization reactions  9.5. Buffer solutions and their importance  9.6. Applications of Acids, Bases and Salts in Daily Life
  10. Solutions and Solubility  10.1. Definition of Solution, Solute, and Solvent  10.2. Factors Affecting Solubility  10.3. Concentration units: molarity and molality  10.4. Saturated, unsaturated and supersaturated solutions  10.5. Concept of osmosis and reverse osmosis  10.6. Concentrative properties of solutions
  11. Gases and Gas Laws  11.1. Properties of gases  11.2. Introduction to Ideal and Real Gases  11.3. Boyle's Law, Charles' Law and Avogadro's Law  11.4. Ideal Gas Equation and Its Applications  11.5. Application of Gas Laws in Real Life
  12. Thermochemistry and energy transformation  12.1. Energy in Chemical Reactions  12.2. Exothermic vs. Endothermic Reactions  12.3. Heat and Enthalpy Changes  12.4. Calorimetry and heat transfer in reactions
  13. Metals and Nonmetals  13.1. Physical and Chemical Properties of Metals and Nonmetals  13.2. Reactivity Series of Metals  13.3. Corrosion and its prevention  13.4. Extraction of metals from ores  13.5. Uses of metals and non-metals in daily life
  14. Introduction to Organic Chemistry  14.1. Characteristics of carbon and organic compounds  14.2. Functional groups and their importance  14.3. Simple Hydrocarbons: Alkenes, Alkenes and Alkynes  14.4. Isomerism in organic compounds  14.5. Introduction to polymers and their uses
  15. Environmental Chemistry and Sustainability  15.1. Green Chemistry Principles  15.2. Effects of Chemical Pollution on Ecosystems  15.3. Acid rain and its effects  15.4. Ozone layer depletion and global warming  15.5. Waste Management and Recycling in Chemistry

Grade 8 ↓


Matter and its properties


Introduction

Matter is all around us. Everything we can see, touch, smell or taste is made up of matter. In simple terms, matter is everything that has mass and occupies space. Understanding matter is a fundamental step in the study of chemistry. In this chapter, we will explore what matter is, the different types of matter and the various properties that define matter.

What is the matter?

Matter is made up of atoms and molecules. An atom is the smallest unit of an element that retains its identity. A molecule is two or more atoms bonded together. Matter exists in various forms, and all of these forms have certain characteristics that can be studied and classified.

Examples of matter around us

Here are some examples of matter:

  • the air we breathe
  • the water we drink
  • The food we eat
  • the clothes we wear

Each of these examples occupies space and has mass, which meets the basic criteria for being classified as matter.

Atom Molecule

States of matter

Matter is usually found in four states: solid, liquid, gas, and plasma. These states depend on the arrangement of atoms and molecules and their energy levels.

Solids

The atoms or molecules in solids are tightly packed together in a certain structure. This gives solids a definite shape and volume. For example, a rock or a book is a solid.

Liquids

In liquids, the atoms or molecules are still close to each other, but they are not in a fixed position. This allows liquids to flow and take the shape of their container, but maintain a constant volume. An example of a liquid is water.

Gases

The atoms or molecules in gases are far apart and move around freely. Gases have no definite shape or volume and they expand to fill their container. Air is an example of a gas.

Plasma

Plasma is a state of matter in which the gaseous state remains active as long as the atomic electrons are no longer attached to a particular atomic nucleus. It is found in stars including the Sun.

Solid liquid Gas Plasma

Properties of matter

Matter has many properties that are classified into two major categories: physical properties and chemical properties.

Physical properties

Physical properties are characteristics of a substance that can be observed or measured without changing the substance's composition. These properties include:

Mass

Mass is the amount of matter in an object. It is usually measured in grams or kilograms. Mass is different from weight because weight is affected by gravity, while mass is not.

Volume

Volume is the space that an object occupies. It is usually measured in liters or cubic meters.

Density

Density is the mass per unit volume of a substance. It is calculated using the formula:

Density = Mass/Volume

Colour

Color is the property we see when light reflects off an object. Color does not affect the chemical composition of a substance.

Dirt

Odor refers to the smell emitted by a substance. Like color, smell does not change the chemical composition of the substance.

Chemical properties

Chemical properties describe the ability of a substance to undergo a chemical change or reaction. These properties include:

Jet

Reactivity is how easily a substance undergoes chemical change. This can include reactions with water, acids, oxygen, etc.

Flammability

Flammability is a measure of how easily a substance catches fire. For example, wood is highly flammable, while metals are not.

pH Levels

The pH level indicates how acidic or alkaline a substance is. It is measured on a scale of 0 to 14, with 7 being neutral.

Mixtures and pure substances

Matter may be classified as a mixture or a pure substance.

Pure substance

Pure substances are made up of only one type of atom or molecule. They have a uniform and definite composition. Elements and compounds are pure substances. For example, H 2 O (water) is a compound and a pure substance.

Mixture

A mixture is a combination of two or more substances that are not chemically bonded. Mixtures can be either homogeneous or heterogeneous.

Homogeneous mixture

Homogeneous mixtures have the same composition. A solution is an example of a homogeneous mixture. Salt dissolved in water forms a salt water solution.

Heterogeneous mixtures

Heterogeneous mixtures do not have a uniform composition, and their parts can be easily identified. A salad is a common example of a heterogeneous mixture.

Element Mixture Homogeneous Heterogeneous

Conclusion

Understanding matter and its properties is vital to chemistry and exploring the natural world. Knowing the states of matter, as well as the physical and chemical properties of matter, provides a foundation for studying more complex chemical reactions and interactions. Overall, matter is a diverse and dynamic element of our universe, appearing in a variety of forms and exhibiting a wide range of properties that impact our daily lives.


Grade 8 → 2


U
username
0%
completed in Grade 8

← Prev (1.5)
Scientific investigation and experimental methods in chemistry
Next (2.1) →
Definition and classification of matter

Comments 



Matter and its properties

https://www.chemistryelite.com/g8/2?ceal=en