Recent content by someth1ng

Personally, I wouldn't make that inference unless it is specified in the syllabus (I wouldn't know if it is) or there is further data analysis. I would simply say that water is unbuffered, so it is more prone to pH changes.

What's the question?

In HS, it's mostly just algebra. At university, you'll need some basic calculus (advanced is probably in Y12). You can probably get to a PhD in chemistry (not necessarily every subdiscipline though) with just 3U maths (all science students have to learn to this level at university).

higher concentration = more heat per unit volume.

C

BTW, in real life, that's definitely not how you should use indicators. I think this is a scientifically bad question. I can argue for practically any answer here. Keep in mind that pink is often considered a light shade of red (and if you dilute a red solution, you'll get pink). A...

The full explanation refers to the Van 't Hoff equation (don't think this is HSC). However, it comes down to this: Increasing temperature will increase the reaction rate for both the forward AND reverse reactions. The activation energy of the reverse and forward reactions are rarely equal. The...

This is a bad question for several reasons. It needs to specify which terminal speed (i.e. with or without the parachute deployed). We can start with velocity, V, which will always be down because the skydiver will always be in free fall (ignoring horizontal movement). If the parachute is...

Q19. M(Ba(OH)2) = 171.23 g/mol n(Ba(OH)2) = (17.1 g)/(171.23 g/mol) = 0.100 mol c(Ba(OH)2) = 0.100 mol/0.100 L = 1.00 M c1v1=c2v2 1.00 M * 0.00500 L = 0.04 M * v2 v2 = 0.125 L = 125 mL As a sanity check, you can see that from 1.00 M to 0.04 M is 25x dilution. So the new volume is 5*25 mL =...

Q11. It's a sealed reaction vessel so none of the details matter apart from the total mass of the starting materials. m(Hg) = 10 mL * 13.546 (g/mL) m(O2) = 150 mL * 0.001429 (g/mL) m(total) = m(Hg) + m(O2) = 135.67 g (i.e. B)

When you neutralise HCl with Na2CO3, you end up with NaCl (aq) and CO2 (g). However, some of the CO2 remains dissolves as carbonic acid, which has a pH around 5.5 (around the same as rainwater).

The marking criteria are wrong, which is kinda sad. The sample answer is solid, though. Chain length results in more dispersion forces, which increase the boiling point.

Are you asking in terms of why it needs to be water and not another solvent, or why there needs to be a solvent at all?

There are many reasons that can be argued. For Cr specifically, a common one is about pairing electrons (i.e. electron repulsion), which is part of it. There are a total of 6 orbitals to fill with 6 electrons (1 s orbital, 5 d orbitals). It just happens that pairing the electrons in the s...

B