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The point of intersection of the two lines is the point at which citric acid and sodium hydroxide are present in their stoichiometric ratio. The increasing trend for lower volumes of citric acid is because the citric acid is the limiting reagent, hence more citric acid means more reaction and...

Yes... you were wrong in the sense of carelessly used terminology. I doubt you actually thought / meant "weaker" but it is a common misconception so I feel the need to jump on it when I see it. :)

Typically, yes, primary amides are at least as soluble as the corresponding carboxylic acid. Secondary amides are less soluble (less H bonding) and tertiary amides are more akin to esters, having dipole-dipole interactions and H-bond acceptors but no H-bond donors.

This one is unusually bad for CSSA standards. Checking thoroughly is not that easy, either - many people wouldn't notice a detail like the mistake in q2 or the flaw in the equilibrium graph.

Solubility will be higher when there are more interactions with water (through H bonding) and lower the more the molecule has regions that can only form dispersion forces (non-polar regions)

Find the concentrations of acetic acid and acetate in the solution from the neutralisation, then put those values as knowns into your Ka - the concentration of the hydronium will be the only unknown.

This is correct, except for in one way that everyone should be careful about, and I've highlighted it in bold. It is correct that the acid has been diluted, so you are titrating with a lower concentration of acid, but its nature / strength is unchanged. You are titrating with a smaller...

Addition needs an alkene. Substitution is typical for haloalkanes and alcohols undergo substitution (along with other reactions)

You should be able to do this, but a surprising number of these types of graphs are drawn incorrectly with the final concentrations wrong. Look at the 2021 CSSA, for example.

The H on OH should appear in hydrogen NMR spectra, somewhere between 1 and 5 ppm (it is difficult to predict). It generally does not cause splitting, however.

Regarding the CSSA 2021 paper, it should be noted that there were a lot of mistakes: In question 2, none of the equations are correct. The answer is meant to be D but there is a typo in the formula for aluminium carbonate. It should be Al2(CO3)3 but has been incorrectly written as Al2(CO2)3...

This thread, to which Trebla referred, contains discussion of every part of the short answer section of the paper including common mistakes. This post in another thread, and subsequent discussion, covers all of the MCQ on the paper. I regret that a full solution file is not completed but every...

Question 33 Average on part (a) was 4.05 / 7 amongst those who attempted it Average on part (b) was 1.267 / 2 amongst those who attempted it Average on part (c) was 1.133 / 3 amongst those who attempted it Average on part (d) was 1.083 / 3 amongst those who attempted it Half of all those who...

Question 32 Average for part (a) was 1 / 1 amongst those who attempted it Average for part (b) was 1.476 / 2 amongst those who attempted it Average for part (c) was 1.474 / 2 amongst those who attempted it Average for part (d) was 1.056 / 3 amongst those who attempted it Part (a) was the...

Question 31 Average for part (a) was 1.87 / 2 amongst those who attempted it Average for part (b) was 1.818 / 3 amongst those who attempted it Part (a) used the standard Ka calculation method on an atypical (non-BL) acid reaction. I was very pleased to see that most people handled this...

Question 30 Average for part (a) was 1.522 / 2 amongst those who attempted it Average for part (b) was 0.565 / 1 amongst those who attempted it Average for part (c) was 1.4 / 2 amongst those who attempted it Average for part (d) was 0.526 / 1 amongst those who attempted it Average for part (e)...

Question 29 This question was done well Average on part (a) was 2.348 / 3 amongst those who attempted it Average on part (b) was 1.625 / 3 amongst those who attempted it For part (a), the species sought were Na+, HCO3-, CO32-, H2CO3, H2O, H3O+, OH-, resulting from dissolution of the sodium...

Question 28 Average on part (a) was 2.13 / 3 amongst those who attempted the question Average on part (b) was 0.818 / 1 amongst those who attempted the question Average on part (c) was 0.9 / 2 amongst those who attempted the question Average on part (a) was 1.143 / 2 amongst those who attempted...

Question 27 Average was 3.952 / 7 amongst those who attempted the question This was an "assess" question, so it required a judgement on the question of the "validity of the conclusion that the zinc smelter is releasing high concentrations of cadmium pollution" that needs to be based on a...

I strongly agree that a lack of definition is part of the problem, but it also doesn't help that most teachers have little experience in these concepts in an authentic research or industrial setting, so they lack the concrete experience to give these terms nuanced meaning. Plus, meaning is...