StoichioAI vs 5

StoichioAI is for Hong Kong secondary chemistry. Students write calculation steps on a whiteboard. The AI reads the working and asks questions, instead of handing over the answer. It is for students preparing for HKDSE Chemistry and for teachers who need to see how their own groups are doing. The interface, topics and AI replies can be switched between Traditional Chinese and English. English uses Hong Kong DSE chemistry wording and British spelling. Students can: Read an interactive lesson, then try the follow-up calculations Write with Apple Pencil or a finger, or submit a photo from the camera or the photo library Ask for a Socratic hint after a wrong attempt. Spoken feedback is Cantonese in Chinese and English in English Review feedback, past attempts, points, and a learning suggestion based on their own weak spots Teachers can: Create a teaching group and invite students with a join code or a school email See weak topics, common mistakes, and each student’s progress Refresh an AI suggestion for the group or for one student Preview questions and reference answers Topics include reacting masses, concentration, pH, volumetric analysis, standard enthalpy changes, Hess's law, rate of reaction, molar volume of gases, equilibrium constant, shifts in equilibrium, organic synthesis calculations, rate equation, activation energy, atom economy, separation and purification, quantitative analysis, instrumental analysis, and analytical chemistry applications. Sign in with an authorised school email. Points are awarded only the first time an exercise is answered correctly.

Prepare for HKDSE Mathematics Compulsory Part with 1,500 original practice questions in English and Traditional Chinese. This Hong Kong secondary maths revision app combines MCQ practice, worked answers, illustrated study notes and a calculator for short daily study sessions. 1,500 QUESTIONS AT THREE LEVELS Choose Easy for foundational skills, Medium for connected calculations and applications, or Hard for DSE-style reasoning. Each level has 500 questions. Practise by topic or mix all three in continuous random practice, without a fixed practice-set length. Every question is a four-option multiple-choice question. NUMBER AND ALGEBRA Revise index laws, surds, factorisation, formula rearrangement, quadratic equations, complex numbers, roots and discriminants. Work with functions and graph transformations, exponential and logarithmic expressions, polynomial division, factors and remainders, direct and inverse variation, percentages, arithmetic and geometric sequences, inequalities and linear programming. GEOMETRY AND TRIGONOMETRY Practise coordinate geometry, gradients, straight lines, circle equations, intersections and tangency. Review circle angles, similarity, Pythagoras, sectors, areas, volumes, solids and loci. Connect triangle ratios with sine and cosine rules, bearings and spatial calculations. Relevant questions include diagrams, tables or graphs. PROBABILITY AND STATISTICS Build confidence with permutations and combinations, sample spaces, complementary events and conditional probability. Revise averages, frequency tables, dispersion, standard deviation, standard scores, grouped-data estimates and interpreting statistical displays. WORKED SOLUTIONS AND MISTAKE REVIEW Check an answer and read the steps behind the result. Save useful questions, add personal notes and track topic progress. The mistake book collects wrong answers. Automatic practice waits 24 hours before repeating a wrong question; you can intentionally retry an unlocked question at any time through the numbered picker. Its colours show your latest correct or wrong result. ILLUSTRATED REVISION NOTES Study 16 bilingual chapters with worked examples, formula and decision tables, common-trap reminders and quick recall quizzes. Open the in-app calculator while practising. Try a 10-question, 20-minute timed mock to work on pacing. This short mock is an app practice format, not a complete HKEAA examination paper. BILINGUAL AND OFFLINE Choose the interface and question languages independently. English and Traditional Chinese questions, diagrams and notes are included in the app for offline revision from first launch. Useful for self-study alongside school lessons and DSE maths revision. PLAN YOUR NEXT REVISION SESSION Use topic filters after a school lesson, then mix levels to check whether you can recognise the right method without a topic prompt. Keep your own written working and compare it with the explanation: look for sign errors, units, omitted conditions and diagram assumptions. Bookmark a useful example, record the step you missed and revisit the matching chapter before your next test. FREE QUESTIONS AND OPTIONAL PREMIUM The first 100 questions are free. Premium unlocks all 1,500 and removes ads, with lifetime, annual or three-month plans. You may instead choose to watch three rewarded ads for 24 hours of full question-bank access. Free use includes banner and occasional full-screen ads; rewarded access does not remove ads. Subscription price and renewal terms are shown before purchase. By Astera Technology Limited. Not affiliated with HKEAA or the Education Bureau. Original practice questions and notes, not official questions or past papers. Covers Mathematics Compulsory Part, not M1 or M2. Support: business@asteratek.com Privacy: https://asteratek.com/app-privacy Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/