Chemistry Grade 10 Notes

Chemistry Grade 10 Notes

Chemistry Grade 10 Notes

Chemistry is a central science essential for understanding the composition, properties of matter and the changes it undergoes. It provides the fundamental basis for competencies in various science and technical fields necessary for industrial and economic growth.

Senior School Grade 10 Chemistry Learning Outcomes

By the end of the Senior School Chemistry course, the learner should be able to:

  • Acquire scientific knowledge, skills, values, and attitudes for everyday use.
  • Conduct a range of scientific investigations, including data collection and interpretation.
  • Use scientific language in the study of Chemistry.
  • Develop skills in logical thinking through project and field work.
  • Relate classroom Chemistry to modern industrial processes and real-world situations.
  • Develop critical thinking skills to explain phenomena and address challenges.
  • Apply principles of Chemistry and acquired skills to invent, construct, or manufacture useful products for sustainable development.

Chemistry Grade 10 Senior School Lesson Notes.

Grade 10 Chemistry Strands

The Senior School Chemistry curriculum is organized into three main strands:

1.0 INORGANIC CHEMISTRY

1.1. Introduction to Chemistry
1.2. The Atom
1.3. The periodic Table
1.4. Chemical Bonding
1.5. Periodicity

2.0 PHYSICAL CHEMISTRY

2.1. Acids and Bases
2.2. Introduction to Salts

3.0 ORGANIC CHEMISTRY

 

StrandFocus
1.0 Inorganic ChemistryIntroduction to Chemistry, The Atom, The Periodic Table, Chemical Bonding, Periodicity.
2.0 Physical ChemistryAcids and Bases, Introduction to Salts.
3.0 Organic ChemistryIntroduction to carbon-containing compounds.

1.0 Inorganic Chemistry

 

Sub-Strand 1.1: Introduction to Chemistry

Meaning of Chemistry

Chemistry is the branch of science that studies matter and its properties, as well as how matter changes and interacts with energy. It focuses on the fundamental building blocks of matter, atoms, and how they combine to form molecules and compounds.

Branches of Chemistry

Chemistry is a vast field, specialized into several main branches:

  • Organic Chemistry: The study of carbon-containing compounds. It is vital for understanding life processes and synthetic materials (e.g., plastics, fuels).

  • Inorganic Chemistry: The study of compounds that generally do not contain carbon, including metals, minerals, and industrial chemicals.

  • Physical Chemistry: Deals with the principles of physics that govern chemical interactions, focusing on energy changes, reaction rates, and the structure of matter.

  • Analytical Chemistry: Involves identifying and quantifying the components of substances (e.g., quality control, environmental testing).

  • Biochemistry: The study of chemical processes within living organisms (e.g., the chemistry of proteins and DNA).

  • Industrial Chemistry: Focuses on the chemical processes involved in large-scale manufacturing of products.

Careers in Chemistry

Studying chemistry opens up diverse career paths, including: Chemical Engineer, Analytical Chemist, Biochemist, Forensic Scientist, Pharmacist, Food Scientist, Environmental Chemist, and Research Chemist.

Sub-Strand 1.2: The Atom

The atom is the basic unit of a chemical element.

(a) Structure of the Atom

An atom consists of a dense, central nucleus surrounded by a cloud of negatively charged electrons.

Subatomic ParticleLocationChargeRole
Protons (p+)NucleusPositive (+1)Determines the Atomic Number (Z), defining the element.
Neutrons (n)NucleusNeutral (0)Contributes to the Mass Number (A).
Electrons (e‾)Orbitals/ShellsNegative (-1)Involved in chemical bonding and reactions.
(i) Atomic Models

  • Dalton’s Model: John Dalton proposed that all matter is made of tiny, indivisible particles called atoms.

  • Rutherford’s Model: Based on Ernest Rutherford’s gold foil experiment, he proposed that the atom has a small, dense, positively charged nucleus at its center, and most of the atom is empty space.

(ii) Atomic Number and Mass Number

  • Atomic Number (Z): The number of protons in the nucleus. It uniquely identifies an element.

  • Mass Number (A): The total number of protons and neutrons in the nucleus.
    Number of Neutrons = A – Z

(b) Relative Atomic Mass of Elements

(i) Isotopes

Isotopes are atoms of the same element that have the same number of protons (Z) but different numbers of neutrons (different mass numbers, A).

(ii) Relative Atomic Mass (RAM)

The Relative Atomic Mass (RAM) of an element is the weighted average of the masses of its naturally occurring isotopes, compared to 1/12th the mass of a carbon-12 atom.

Formula for Relative Atomic Mass RAM:
RAM = [(% Abundance of Isotope 1 × Mass of Isotope 1) + (% Abundance of Isotope 2 × Mass of Isotope 2) + …] / 100

(c) Electron Arrangement using s orbital and p orbital

(i) Energy Levels and Orbitals

Electrons are arranged in specific energy levels (shells), which are further divided into orbitals. Orbitals are regions of space where there is a high probability of finding an electron.

  • s orbital: Spherical in shape. Each s orbital can hold a maximum of 2 electrons.
  • p orbitals: Dumbbell-shaped. There are three p orbitals in each energy level (except the first one), oriented along the x, y, and z axes (px, py, pz). Each p orbital can hold a maximum of 2 electrons, so a set of three p orbitals can hold a total of 6 electrons..
(ii) Order of Filling Electrons (Aufbau Principle)

Electrons fill atomic orbitals in order of increasing energy. For the first 20 elements, the filling order is:

1s, 2s, 2p, 3s, 3p, 4s

(iii) Writing Electron Arrangement using s and p Notation

The electron arrangement (or electron configuration) shows how electrons are distributed among the orbitals in an atom. The notation indicates the principal energy level (n), the type of orbital (s or p), and the number of electrons in that orbital as a superscript.