Thanks for the suggestion. I've considered comparing two approaches for other experiments but hadn't for kinetics.
Internal AssessmentYou raise a very good point, Austin. This question relies on an oversimplification of the model ('Weak acids have strong conjugate bases" is not correct; I like your correction). We've simplified the model to help with understanding, but in this case,...
MC test: R3.1 (AHL) pOH, Ka, Kb, pKa and pKbHi I am very surprised to see the following answers in the May 2026 P2 TZ1 answer that in 3(c)(ii), the IB does not accept probability of collision on effect of increase temp on rate. However in the IB guide, it is clearly written...
R2.2 Rate of reaction & collision theoryMost of my students chose option D for question 6, and I think it is probably the most appropriate answer following the IB guidance of choosing the "best" option. However, I'm wondering if there is potential for confusion amongst more careful...
MC test: R3.1 (AHL) pOH, Ka, Kb, pKa and pKbThanks for this contribution John. It is a subtle point that 2A is not the same as A2 but it is important in terms of arriving at the overall equation. Thank you for noticing it and for pointing it out. It is changed now.
Printable versions of written tasksHi Demet, No you are not missing anything! My mistake as magnesium sulfate is very soluble in water. I've corrected it now.
R3.1 Neutralization reactionsR2.2 (HL) Reaction mechanisms Question #4. viiI really like this challenging problem.For step 3 of the proposed mechanism (when the orders are 3 and zero) I believe the A2 should be...
Printable versions of written tasksHi. In the short answer questions paper, #6 , reaction between MgO and sulfuric acid should produce Mg sulfate (aq), but in the answers it says Mg sulfate in solid state produced. Isn't it highly soluble in water (epsom salt)? Am I missing something?...
R3.1 Neutralization reactionsHi Mani,If this is for an IA I suggest your student searches for "Is the rate of electrolysis dependent upon the concentration of the electrolyte? They will find that there are many articles discussing this.
R3.2 Electrochemical cells
Geoffrey
Site authorHi Austin, As Paul has already said your comments are very valid. I've altered the question so that it only refers to very weak acids and given some more detail in the answer. Thank you for your input.
MC test: R3.1 (AHL) pOH, Ka, Kb, pKa and pKb