Chemistry 1

HIGHER SECONDARY CERTIFICATE 2028 Science Group • English Version • Dhaka Education Board Chemistry First Paper Subject Code 176 Complete Chapter Notes Full syllabus • Labelled diagrams • Board style questions Prepared by Md Ahbab Hamid Khan ahbab.tech November 8, 2026

HSC 2028 • Chemistry First Paper • Code 176 1 Contents Examination Structure and Mark Distribution 4 1 Safe Use of Laboratory 5 1.1 Chapter overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 Syllabus coverage and mark allocation . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.3 Hazard classes, symbols, and safety data sheets . . . . . . . . . . . . . . . . . . . . . 5 1.4 Personal protective equipment, safety rules, and storage . . . . . . . . . . . . . . . . 7 1.5 Fire safety and fire extinguishers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.6 Laboratory first aid procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.7 Chemical waste disposal and green laboratory practices . . . . . . . . . . . . . . . . 10 1.8 Volumetric apparatus, glassware cleaning, and heating methods . . . . . . . . . . . . 11 1.9 Analytical balances and accurate weighing . . . . . . . . . . . . . . . . . . . . . . . . 12 1.10 Macro, semi-micro, and micro analytical methods . . . . . . . . . . . . . . . . . . . . 14 1.11 The mole and the Avogadro constant . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.12 Concen

HSC 2028 • Chemistry First Paper • Code 176 2 2.14 Chapter 2 cheat sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 3 Periodic Properties of Elements and Chemical Bonding 50 3.1 Chapter overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 3.2 Syllabus coverage and mark allocation . . . . . . . . . . . . . . . . . . . . . . . . . . 50 3.3 The modern periodic table and block classification . . . . . . . . . . . . . . . . . . . 51 3.4 Block-wise descriptive chemistry (s, p, d, f blocks) . . . . . . . . . . . . . . . . . . . . 51 3.5 Acid-base nature and hydrolysis of Period 3 oxides and chlorides . . . . . . . . . . . 53 3.6 Effective nuclear charge and shielding . . . . . . . . . . . . . . . . . . . . . . . . . . 54 3.7 Periodic trends: radius, ionisation energy, electron affinity, and electronegativity . . 55 3.8 Transition elements, Crystal Field Theory, and coordination chemistry . . . . . . . . 57 3.9 Chemical bonding: ionic, covalent, and coordinate bonds . . . . . . . . . . . . . . . . 58 3.10 Hybridisation and VSEPR molecular geometry . . . . . . . . . . . . . . . . . . . . . 61 3.11 Bond polarity, dipole moment,