Grade 10
Chemistry
Complete Study Notes & Exam Guide
Concise theory, key definitions, formulae, worked examples and practice questions with
answers
9 chapters | Formula sheet | Revision checklist
,Grade 10 Chemistry | Complete Study Notes
Contents
Atomic Structure 3
The Periodic Table 5
Chemical Bonding 7
Stoichiometry and the Mole Concept 9
Acids, Bases and Salts 11
Rates of Reaction and Chemical Equilibrium 13
Redox and Electrochemistry 15
Organic Chemistry 17
Environmental Chemistry 19
Quick Formula Sheet 21
How to use these notes
Read each chapter once, then use the blue boxes as your quick-revision summary.
Amber boxes show common exam traps and mark-scoring tips.
Attempt the practice questions at the end of each chapter before checking the answers.
The formula sheet and revision checklist at the end are designed for last-day revision.
Page 2
, Grade 10 Chemistry | Complete Study Notes
Chapter 1
Atomic Structure
Everything around us is made of atoms. Understanding the structure of the atom explains the periodic
table, bonding and chemical reactions.
1.1 Subatomic Particles
Particle Symbol Relative charge Relative mass Location
Proton p+ +1 1 Nucleus
Neutron n 0 1 Nucleus
Electron e- -1 1/1840 (negligible) Shells around nucleus
Key Definitions
Atomic number (Z) = number of protons (also electrons in a neutral atom).
Mass number (A) = protons + neutrons.
Number of neutrons = A - Z.
Isotopes = atoms of the same element with the same atomic number but different mass numbers
(different neutrons).
1.2 Electronic Configuration
Electrons occupy shells (energy levels) around the nucleus. The maximum number of electrons in a
shell is 2n2: 2 in the 1st shell, 8 in the 2nd, 18 in the 3rd. For the first 20 elements, fill 2, 8, 8, 2.
Element Z Configuration Group Period
Hydrogen 1 1 1 1
Carbon 6 2, 4 14 (IV) 2
Oxygen 8 2, 6 16 (VI) 2
Sodium 11 2, 8, 1 1 3
Chlorine 17 2, 8, 7 17 (VII) 3
Calcium 20 2, 8, 8, 2 2 4
Rule: the number of outer-shell (valence) electrons gives the group number (for groups 1 and 2, and
13-18 as units digit); the number of occupied shells gives the period.
1.3 Isotopes and Relative Atomic Mass
Relative atomic mass (Ar) is the weighted average mass of an element's isotopes compared to 1/12
of a carbon-12 atom.
Page 3
Chemistry
Complete Study Notes & Exam Guide
Concise theory, key definitions, formulae, worked examples and practice questions with
answers
9 chapters | Formula sheet | Revision checklist
,Grade 10 Chemistry | Complete Study Notes
Contents
Atomic Structure 3
The Periodic Table 5
Chemical Bonding 7
Stoichiometry and the Mole Concept 9
Acids, Bases and Salts 11
Rates of Reaction and Chemical Equilibrium 13
Redox and Electrochemistry 15
Organic Chemistry 17
Environmental Chemistry 19
Quick Formula Sheet 21
How to use these notes
Read each chapter once, then use the blue boxes as your quick-revision summary.
Amber boxes show common exam traps and mark-scoring tips.
Attempt the practice questions at the end of each chapter before checking the answers.
The formula sheet and revision checklist at the end are designed for last-day revision.
Page 2
, Grade 10 Chemistry | Complete Study Notes
Chapter 1
Atomic Structure
Everything around us is made of atoms. Understanding the structure of the atom explains the periodic
table, bonding and chemical reactions.
1.1 Subatomic Particles
Particle Symbol Relative charge Relative mass Location
Proton p+ +1 1 Nucleus
Neutron n 0 1 Nucleus
Electron e- -1 1/1840 (negligible) Shells around nucleus
Key Definitions
Atomic number (Z) = number of protons (also electrons in a neutral atom).
Mass number (A) = protons + neutrons.
Number of neutrons = A - Z.
Isotopes = atoms of the same element with the same atomic number but different mass numbers
(different neutrons).
1.2 Electronic Configuration
Electrons occupy shells (energy levels) around the nucleus. The maximum number of electrons in a
shell is 2n2: 2 in the 1st shell, 8 in the 2nd, 18 in the 3rd. For the first 20 elements, fill 2, 8, 8, 2.
Element Z Configuration Group Period
Hydrogen 1 1 1 1
Carbon 6 2, 4 14 (IV) 2
Oxygen 8 2, 6 16 (VI) 2
Sodium 11 2, 8, 1 1 3
Chlorine 17 2, 8, 7 17 (VII) 3
Calcium 20 2, 8, 8, 2 2 4
Rule: the number of outer-shell (valence) electrons gives the group number (for groups 1 and 2, and
13-18 as units digit); the number of occupied shells gives the period.
1.3 Isotopes and Relative Atomic Mass
Relative atomic mass (Ar) is the weighted average mass of an element's isotopes compared to 1/12
of a carbon-12 atom.
Page 3
