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Thanks!

When do we get them? Do different courses get them at different times? They only gave me access to my MyUni account on enrollment day. Anyway, see you guys when classes start!

It's sent today but I changed my address on UAC yesterday. Are they going to send it to my new address or my old one? Since the change was made only yesterday.

re: HSC Physics Marathon Archive A man throws a rock vertically and it reaches a height of 20m. Acceleration due to gravity on the moon is 1.6ms-2. What is the speed at which it was thrown on the moon?

re: HSC Chemistry Marathon Archive Well, 2molL-1 of anything is concentrated, no?

re: HSC Chemistry Marathon Archive When an acid is defined as strong, it means the acid ionises completely in solutions, such as HCL. Concentrated is used when an acid has a high concentration, such as 2molL-1, regardless of the degree of ionisation.

re: HSC Chemistry Marathon Archive a)CaCO3 + 2HCL ---> CaCl2 + CO2 + H20 b)Concentration = No.of moles/Volume of solution(C=n/V, becomes n=CV), so n=1 x 0.0112L = 0.0112 moles of NaOH c)0.036 moles?(not sure so I left the working out) d)0.014 moles?(again, not sure so I left the working out)...

re: HSC Chemistry Marathon Archive A salt bridge is responsible for allowing the movement of ions between the half cells and for maintaining neutrality of the half cells. For example, if one half cell, say Zn electrode in Zn2+ electrolyte(let the other half cell be anything under Zn). When the...

re: HSC Chemistry Marathon Archive (a) Identify whether the salt, sodium hydrogen carbonate is acidic, basic or neutral. Write a balanced equation to explain its acidic, basic or neutral nature in water. - Looking at the above equations, this salt can be both acidic and basic. How do we...

re: HSC Chemistry Marathon Archive So how do we know if its accepting or donating? Again, HCO3- is a good example. HCO3- in water can be written as HCO3- + H20 ---> H2C03 + OH- (solution becomes basic) or HCO3- + H20 ---> C032- + H30+(solution becomes acidic) Unless you know by heart its...

re: HSC Chemistry Marathon Archive How do we know if a substance in going to be basic, acidic or neutral in water? For example, HCO3-, takes an H+ from water and OH- ions are formed, making the solution basic. How do we know if a substance is accepting or donating protons to water?

Re: HSC 2012 Chemistry Marathon I can't believe I forgot its MOLAR..... thanks guys!

Re: HSC 2012 Chemistry Marathon Thank you so much for your input, especially the effects of acid rain! Now, for mine! Assess the need to monitor levels of lead ions in substances used in society and describe appropriate technologies that can be used for such measurements. - [7 marks] Lead, a...

Re: HSC 2012 Chemistry Marathon Yes! Reason? Because I thought molar heat of combustion was defined as the amount of energy 1g of substance blah blah...?

Re: HSC 2012 Chemistry Marathon Now a big marker: Evaluate the impact of industrial sources of sulfur dioxide and nitrogen oxides on the environment, making use of appropriate chemical equations. (7) Industrial sources of sulfur dioxide and nitrogen oxides(NOx) have a huge impact on the...

re: HSC Chemistry Marathon Archive A certain solution has 10 times the hydrogen ion concentration of a solution of pH 8. What is the pH of the MORE acidic solution? (This is the whole question, no diagrams,no continuation etc) A) 0.8 B) 4 C) 7 D) 9 The answer is given as D, which makes no...

re: HSC Chemistry Marathon Archive Oh I see! They both started with the same amount but when H2S is finished only half of S02 is used, so H2S is limited. Is this correct?

re: HSC Chemistry Marathon Archive S02 and H2S both have the same amount of moles. How do you work out which one is the limiting reagent?

re: HSC Chemistry Marathon Archive What mass of sulfur is formed when 2L of sulfur dioxide is mixed with 2L of hydrogen sulfide, under standard conditions(273K and 100kPa)? SO2 + 2H2S --> 3S + 2H20 What I got so far: Let X be moles of SO2 or H2S, so X=2/24.79=0.08moles. My question is, do we...

re: HSC Chemistry Marathon Archive Oh that's great news! Anyway, I got it off a CSSA paper, so that explains it