# Search results

1. ### Tutorials before Lectures?

Timetables got released yesterday and there's a trend in my timetable where my tutorials are conducted before my lectures. Is this normal? I thought tutorials are where you ask questions based from your lectures, so would it still work out if my tutorials are before lectures? Advice would be...
2. ### Equilibrium Constant & Temperature

Why does the equilibrium constant get affected only by changes in temperature? Why not with changes in pressure or concentration? Let's consider a general reaction: A + B <--> C + D where Δ < 0 The eq. constant expression would be [C][D]/[A]. If we were to increase the temperature, equilibrium...
3. ### Calorimetry

Using the equation Q = mcΔt, if Q is positive; the reaction is said to be endothermic. If Q is negative, the reaction is said to be exothermic. What confuses me is that when we perform the experiment in school, we pour an Ionic compound into a beaker filled with water and measure the final and...
4. ### New Syllabus - Scaling

Considering the new syllabus for Science and English have become considerably harder than the old syllabus, does this mean that Physics, Chemistry, Bio and English will generally get scaled higher compared to before? Or does it depend more on how everyone does in the 2019 HSC?
5. ### Concentration/Mass Question

Need help with these. If someone could explain (worked solution) the answers to these, it’d be greatly appreciated. Thanks. 1)A beaker contains 100mL of Silver Sulfate solution at a concentration of 1.0 x 10^-6 mol/L. What is the mass of Silver ions in the beaker? Answer: 2.16 x 10^-4 g 2)...
6. ### US Tariff and how it impacts domestic steel price

My teacher was telling us about how due to the tariff the US put on steel and aluminium imports, the price of both of them would increase (which makes sense). But he then said that domestic suppliers would also increase supply AND increase the price, meaning the overall price of steel and...
7. ### Questions to 99.95 ATAR Recipients

(Note these questions aren’t ONLY being asked to 99.95 ATAR recipients, if you also have some advice to share - feel free to do so, thanks). Had some questions for the top students, would like some advice: 1) Were you guys always top in your cohort (this doesn’t really apply to Top 25 SS...
8. ### Phys/Chem Questions

Got a few questions I was wondering on. 1) How does the aluminium oxide layer prevent oxidation and why is Aluminium foil good for food? 2) How does the wall exert a force let alone an equal one on a ball? Isn't it F=Ma and the Mass are different for each? How can a stationary object exert a...
9. ### Aerospace Engineering

So I've always had an interest in planes and spacecraft, so from a really early point in my life I had decided to pursue a career in Aeronautical/Aerospace Engineering. But as the HSC is slowly approaching, I was wondering whether it'd be a good Engineering career to choose (especially in...
10. ### Newton's Laws - Examples

1) Say there are two cars; one with a force of 400N and the other one at 800N. Their masses are the same, therefore they have different acceleration. If they were to collide head on and the drivers weren't wearing seatbelts, would the driver from Car A (400N) fly backwards with the car or would...
11. ### Air Resistance & Terminal Velocity

So we all know that if we dropped a feather and a bowling ball from the same height, the bowling ball would land much quicker since the feather has a larger surface area and the air molecules make it "float" more (that's what I learnt from my Science teacher, so correct me if that's wrong). Now...
12. ### Question on Diatomic Oxygen/Reaction

So since Oxygen is a Diatomic gas, how come the Chemical Equation to obtain H2O is H2 + O ---> H2O? Why isn't it H2 + O2 ---> H2O? I understand that the second equation is unbalanced and the product would be 2H2O, but that product isn't normal water anymore; it's something called "Heavy water"...
13. ### Reactivity

How does the unstable valence shell determine the Boiling/Melting point (this is more based on bonds), electrical conductivity and properties for an Element? For example, Hydrogen is highly flammable. But people say it's due to the unstable valence shell. How does the unstable valence shell...
14. ### Why is Mercury liquid at room temperature?

I understand that Mercury has a full outer 6s shell, meaning it doesn't want to share Electrons. Firstly, why isn't it a Noble gas then? Aren't noble gases the most stable elements (Ik that Mercury isn't a gas at room temp, but still). Secondly, I tried searching up why Mercury is a...
15. ### Why is (h,k) the 'Point of Inflection' and 'Centre' in Cubics and Circles?

As the title states, why is (h,k) the POI (Point of Inflection) and Centre in Cubics and Circles? I understand why they're there for Parabolas (have to find the maximum/minimum value), but what's the reasoning behind Circles and Cubics? For a Cubic in y = a(x-h)^3 +k form, there are no maximum...
16. ### Polyatomic Ions

My teacher told me that we need to memorise Polyatomic Ions for the HSC, so my question was; how many of them do we need to memorise? Usually, people give a select few (maybe 10-15) but those vary from different sources, so how many and which ones should I try and memorise?
17. ### Chem Question

How does one determine the charge of a Polyatomic ion? My teacher said that we don't learn how to find the charge so it's better to memorise them. But is there a way to determine the charge?
18. ### Chemistry Questions - Help

Hi, I've got a few questions on Electronic configurations of Atoms and would appreciate if you guys could help me out: 1) So there are 4 shells which are configured as 2,8,8,8 correct? But I read somewhere in my textbook something about it being configured as 2,8,18,32 so how come it's...
19. ### Year 11 and 12 Study Tips

So as Prelims are slowly approaching, I was looking for some 'study tips'. Nowadays I usually wait until the last two-three days (a week if it's Math) to study for an upcoming test. I usually do my assignments on the last day (very bad, I know). Although you guys may think I have the worst...
20. ### Genes

So we all know that a human has 46 Chromosomes, but wouldn't there be billions, maybe trillions of Chromosomes in the ENTIRE human body? Or does each cell have 46 of the same Chromosomes as there are in the other cells, so we only have 46 DIFFERENT Chromosomes? Another question I have is...