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Changes in H2 Chemistry syllabus 2017 – part 1

Mr Khemistry

Theories of acids and bases *New!
Arrhenius theory – acid produce H+ in water, base produces OH in water.
Bronsted Lowry theory – acid produces H+, base accepts H+. Conjugate pair concept.
Lewis theory – acid as electron pair acceptor, base as electron pair donor.

Gases: Vm = 22.7 dm3 at stp (1 bar, 273 K), 24 dm3 rtp (1 atm, 293 K)

Group 2 & 17 (no longer Roman Numerals) now under Periodicity.

Group 17: Not required to describe the reactions of halide ions with sulfuric acid. Not required to describe the reaction of chlorine with cold and hot aqueous sodium hydroxide.

Group 2: learn thermal stability of carbonates instead of nitrates.

Equilibria: Show understanding that the position of equilibrium is dependent on the standard Gibbs free energy change of reaction, ΔG.
ΔG < 0 means forward reaction is spontaneous (equilibrium constant is >> 1, position of equilibrium lies to the right), > 0 means forward reaction is not spontaneous but backward reaction is (equilibrium constant is < 1, position of equilibrium lies to the left). ΔG = 0 means the system is at equilibrium.

Part 2 here

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Changes in weightage for H2 Chemistry syllabus 2017

Mr Khemistry

‘A’ Level Chemistry Syllabus

Overview of changes in weightage:

A level H2 Chemistry weightage

Table showing weightage

Table taken from SEAB website

All students required to take practical paper 4, including private candidates.

This means that candidates retaking their A level chemistry paper this year will have to sit for a 20{8445fa0408f68c331c03e03f10d6a7bff33fb7168cc52e9b2191ddf5ec3671a6} weightage practical paper.
Also, their previous SPA scores will not be counted.

So you are a private student retaking A level H2 chemistry this year, do try to enroll yourself in a private school which provides practical lessons.

‘A’ Level Chemistry Syllabus weightage

Paper 1 will be 30 MCQ (with 5-8 Multiple Completion Type) instead of 40 MCQ (10 MCT). Lower weightage.

Paper 2 data-based question will be 20-25 marks out of 75 instead of 15-20 marks out of 72, which gives it a higher weightage.

Planning question shifted from Paper 2 to Paper 4. Weightage is similar ~11/12 marks.

Paper 3 now has two sections, Section A 60 marks of 3-4 compulsory questions. Section B 20 marks, choose one of two questions.
Previously students choose 4 of 5 20 mark questions.
This means that there is lesser chances of avoiding a certain topic since bulk of the questions are compulsory.
Questions will include different topics.

Overall, 5{8445fa0408f68c331c03e03f10d6a7bff33fb7168cc52e9b2191ddf5ec3671a6} of weightage shifted over from MCQ to Paper 2.

There is a shift away from remembering large chunks of information and a shift toward application of knowledge.
Hence there is a real need to guide students to often and consciously apply their knowledge to unfamiliar contexts.

Return to Home to find out more about H2 Chemistry Tuition in Singapore with Mr Khemistry.

Why do we use only sulfuric acid for permanganate titrations?

Mr Khemistry

Permanganate titration

Qn: Why can’t we use hydrochloric acid or nitric acid for manganate (VII) redox titrations?

Ans: For HCl, the chloride ion will be oxidised to chlorine gas by manganate (VII) ion.

HNO3 is also an oxidising agent and hence would compete with permanganate.

Lastly, permanganate cannot oxidize sulfate ion and sulfuric acid is not an oxidizing agent.

Therefore, sulfuric acid is the mineral acid of choice for manganate (VII) titrations.

More common questions here.

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June Intensive Revision Programme

Mr Khemistry

J2 students, need some last minute help in Organic Chemistry before your Mid-Year Exams?

Sign up for 4 lessons of intensive revision using 2016 Prelim structured questions from different JCs! Part 1 of our revision program covers the whole spectrum of organic concepts so do come prepared 🙂 Answers will be analysed together and misconceptions will be addressed on the spot.

Dates: 7, 9, 14, 16 June
Time: 2 – 5 pm
Venue: Bukit Timah Shopping Centre unit B2-13C

MCQ and Data-based organic questions will be covered under part 2 of our revision programme.

Dates: 21 and 23 June
Time: 2 – 5 pm
Venue: Bukit Timah Shopping Centre unit B2-13C

J1 students, stressed by your first JC major exam?

Sign up for our J1 revision program covering the core topics, Mole Concept, Gases, Chemical Bonding, Atomic Structure and Redox.

Dates: 5, 12, 19 June
Time: 10 – 1 pm
Venue: Bukit Timah Shopping Centre unit B2-13C

Contact us at enquiry@mrkhemistry.com or SMS/whatsapp us at 98537960 to register for your place today!

ps: Remember to bring along a sweater, it can get cold 🙂

3 Tips For Understanding Chemistry

Mr Khemistry

Tips for Studying Chemistry

Let’s face it, chemistry is not the easiest subject to master. It’s abstract concepts (think atoms and molecules) which you can’t see with your eyes. So here i will share with you all 3 tips for studying chemistry.

Tip

#1: Search for Youtube videos to help you visualize spatial ideas such as atomic orbitals or shape of molecules.

#2: Ask your teacher if there’s any suitable analogies to help you understand the concept e.g. making Subway sandwich for understanding rate-determing step

#3: Play with physical models such as those by Molymod, we happen to have a set here at Khemistry so do drop by if you want use it 🙂

All the best for your Chemistry and click here for more tips!

Remember, CHEMISTRY!
Mr Khemistry

More tips here!

Home of Leading Chemistry Tuition Singapore

picture of personal schedule - Mr Khemistry

New! 2017 Time-table

Mr Khemistry

Bukit Timah Shopping Centre

Class Timings:

JC 2: Saturday, 230 – 430 pm

JC 1: Sunday, 2 – 4 pm 

Register for your slot today!

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