# Your Science Online > Free IGCSE, GCSE and A Level science notes, calculators and study guides, plus online 1-to-1 Chemistry, Biology and Physics lessons with Ms. Humaira Asim, a science teacher with 15+ years of experience. > Generated by All in One SEO v5.0.5, this is an llms.txt file, used by LLMs to index the site. ## Sitemaps - [XML Sitemap](https://yourscienceonline.com/sitemap.xml): Contains all public & indexable URLs for this website. ## Posts - [Blog](https://yourscienceonline.com/blog/): Study guides and exam tips for IGCSE, GCSE and A Level science students, from choosing Combined or Triple Science to fixing common Chemistry mistakes. - [Can You Do A Level Chemistry After Combined Science?](https://yourscienceonline.com/a-level-chemistry-after-combined-science/): Often yes, but it depends on your grades and sixth form. Learn what to check, which gaps to fill and how to prepare for A Level Chemistry. - [5 Common IGCSE Chemistry Calculation Mistakes (and How to Fix Them)](https://yourscienceonline.com/igcse-chemistry-calculation-mistakes/): Avoid the five most common mole calculation mistakes in IGCSE Chemistry, with wrong-and-right worked examples, a quick checklist and tips to protect your marks. - [Revision Plan for Cambridge IGCSE Chemistry (0620)](https://yourscienceonline.com/revision-plan-for-cambridge-igcse-chemistry-0620/): A simple four-week revision plan for Cambridge IGCSE Chemistry 0620: what to study each week, a daily routine, revision methods and exam tips. - [Combined Science or Triple Science? The Difference Explained (GCSE and IGCSE)](https://yourscienceonline.com/combined-science-or-triple-science-the-difference-explained-gcse-and-igcse/): Combined Science or Triple Science? Learn how the two GCSE and IGCSE science routes differ, how they are graded and how to choose the right one for you. ## Pages - [Home](https://yourscienceonline.com/): Online Chemistry, Biology, Physics and Combined Science classes for IGCSE, GCSE, A Level, O Level, IB and AP with Ms. Humaira Asim. Free notes and calculators. - [Cambridge IGCSE Chemistry 0620: The Mole and Stoichiometry Notes](https://yourscienceonline.com/igcse-chemistry-0620-mole-stoichiometry/): Free Cambridge IGCSE Chemistry 0620 notes on the mole, Avogadro constant, reacting masses, gas volumes, concentration and titrations, with a mole calculator. - [Combined Science Notes](https://yourscienceonline.com/notes-2/combined-science/): Free GCSE and IGCSE Combined Science notes for Biology, Chemistry and Physics, with worked examples, diagrams, calculators and practice questions. - [Chemistry Notes](https://yourscienceonline.com/notes-2/igcse-chemistry-notes-topic-by-topic/): Free Cambridge IGCSE Chemistry 0620 notes, topic by topic, including atomic structure and the mole, with worked examples, calculators and exam tips. - [Cambridge IGCSE Chemistry 0620: Electrolysis Notes](https://yourscienceonline.com/igcse-chemistry-0620-electrolysis/): Free Cambridge IGCSE Chemistry 0620 electrolysis notes: anode and cathode, predicting products, brine, copper(II) sulfate, half-equations and electroplating. - [Cambridge IGCSE Biology 0610: Cells and Cell Structure Notes](https://yourscienceonline.com/igcse-biology-0610-cells-cell-structure/): Free Cambridge IGCSE Biology 0610 notes on cell structure: labelled animal, plant and bacterial cells, specialised cells and magnification, with practice. - [Biology Notes](https://yourscienceonline.com/notes-2/biology/): IGCSE Biology topics taught at Your Science Online: cells, transport in cells, enzymes, nutrition and genetics. Free notes are added topic by topic. - [Cambridge IGCSE Biology 0610: Diffusion, Osmosis and Active Transport Notes](https://yourscienceonline.com/igcse-biology-0610-diffusion-osmosis-active-transport/): Free Cambridge IGCSE Biology 0610 notes on diffusion, osmosis and active transport, with diagrams, a diffusion simulation, quiz and the potato practical. - [Notes](https://yourscienceonline.com/notes-2/): Free IGCSE, GCSE and A Level science notes for Chemistry, Biology and Physics, written by an experienced teacher, with worked examples and practice. - [Physics Notes](https://yourscienceonline.com/notes-2/physics/): Free IGCSE Physics notes by topic, starting with speed, velocity and acceleration. Covers motion, forces, energy, waves and electricity. - [Periodic Table](https://yourscienceonline.com/periodic-table/): Interactive periodic table of elements for IGCSE, GCSE and A Level students. Click or tap any element to see its details. - [Physics Calculator](https://yourscienceonline.com/physics-calculator/): Free online physics calculators for IGCSE, GCSE and A Level students. Quick answers to help you check your working and revise. - [Biology Calculator](https://yourscienceonline.com/biology-calculator/): Free online Biology calculators for IGCSE, GCSE and A Level students. Quick answers to help you check your working and revise. - [Chemistry Calculator](https://yourscienceonline.com/chemistry-calculator/): Free online chemistry calculators for IGCSE, GCSE and A Level students. Quick answers to help you check your working and revise. - [Contact Us](https://yourscienceonline.com/contact-us/): Book a 1-to-1 online science lesson with Ms. Humaira Asim for IGCSE, GCSE, A Level, IB or AP Chemistry, Biology and Physics, in any time zone. - [About Us](https://yourscienceonline.com/about-us/): Meet Ms. Humaira Asim, a science teacher with 15+ years of experience teaching IGCSE, GCSE, A Level, IB and AP Chemistry, Biology and Physics online. - [Online Science Tutor for New Zealand](https://yourscienceonline.com/online-science-tutor-new-zealand/): Online Cambridge IGCSE, A Level and IB Chemistry, Biology and Physics lessons with Ms. Humaira Asim for students in New Zealand, at times that suit you. - [Online Science Tutor for Hong Kong](https://yourscienceonline.com/online-science-tutor-hong-kong/): Online IGCSE, IB and A Level Chemistry, Biology and Physics lessons with Ms. Humaira Asim for students in Hong Kong, at times that suit your school week. - [Online Science Tutor for Singapore](https://yourscienceonline.com/online-science-tutor-singapore/): Online O Level, IGCSE, IB and A Level Chemistry, Biology and Physics lessons with Ms. Humaira Asim for students in Singapore, at times that suit you. - [Online Science Tutor for the UK](https://yourscienceonline.com/online-science-tutor-uk/): Online GCSE, IGCSE and A Level Chemistry, Biology and Physics lessons with Ms. Humaira Asim for AQA, Edexcel and OCR students across the UK. - [Online Science Tutor for the Middle East](https://yourscienceonline.com/online-science-tutor-middle-east/): Online IGCSE, IB and A Level Chemistry, Biology and Physics lessons with Ms. Humaira Asim for students in the UAE, Saudi Arabia, Kuwait, Qatar and Bahrain. - [Cambridge IGCSE Physics 0625: Forces, Resultant Force and Vectors Notes](https://yourscienceonline.com/igcse-physics-0625-forces-resultant-force-vectors/): Free Cambridge IGCSE Physics 0625 notes on forces: resultant force, F = ma, weight, vectors and Hooke’s law, with diagrams, worked examples and practice. - [Cambridge IGCSE Physics 0625: Speed, Velocity and Acceleration Notes](https://yourscienceonline.com/igcse-physics-0625-speed-velocity-acceleration/): Free Cambridge IGCSE Physics 0625 notes on speed, velocity and acceleration, with distance-time and speed-time graphs, worked examples and practice questions. - [Cambridge IGCSE Chemistry 0620: Atomic Structure Notes](https://yourscienceonline.com/cambridge-igcse-chemistry-0620-atomic-structure-notes/): Free Cambridge IGCSE Chemistry 0620 atomic structure notes: protons, neutrons, electrons, isotopes and electronic configuration, with worked examples. - [Privacy Policy](https://yourscienceonline.com/privacy-policy/): How Your Science Online collects, uses and protects your information, including cookies and Google ads, plus the terms of use for this website. ## Categories - [Blog](https://yourscienceonline.com/category/blog/): Your blog category - [Exam Tips](https://yourscienceonline.com/category/exam-tips/)