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  1. someth1ng

    entropy

    Number of moles for NH3 must be one.
  2. someth1ng

    short answers and long responses

    The most common mistake I have seen is passive voice. It's almost always better to use active voice.
  3. someth1ng

    Why are tertiary alcohols more reactive than primary alcohols?

    Honestly, I simply hate phrasing it as "tertiary alcohols are more reactive than primary alcohols". Why? It is completely reaction-dependent and absolutely incorrect to answer this question without referring to the exact reaction you are looking at. For example, tertiary alcohols are far less...
  4. someth1ng

    HNMR and CNMR

    No. The good thing is that in real life, you're much more likely to know the expected structure and NMR is used to confirm the structure.
  5. someth1ng

    Yelp mindblanked

    They can form hydrogen bonds, but simple esters lack a hydrogen bond donor (i.e. no hydrogen bonded to oxygen/nitrogen/fluorine), so they can't form H-bonds with each other.
  6. someth1ng

    need assistance with part b thanks

    Correct. You can titrate ethanoic acid and sodium hydroxide (i.e. question is just...wrong). The weak acid is in dynamic equilibrium, so as you neutralize with NaOH, more H+ will be made until all acid has become sodium acetate. NaOH and acetic acid will give an equivalence point at pH ~9...
  7. someth1ng

    Quick q can someone recap me on why only temperature affects keq

    In LCP, you can think of energy as a reagent and increasing temperature is adding more energy to the system. If you really want to have more specifics (beyond LCP), you'll need to see the Van 't Hoff equation.
  8. someth1ng

    What is a softening point in terms of polymers?

    You're looking for something like the Vicat softening point. There are a few different tests that will give somewhat different results...they are arbitrary.
  9. someth1ng

    Are addition polymers composed of 3 or more copolymers common?

    Definitely much less common than one or two monomers. In reality, almost all polymers you use have just a single monomer (PE, PVC, PET, PP, PS, PTFE).
  10. someth1ng

    had a few questions

    You're right. Also, the K should be capitalised because the lower-case (k) is for rate constants.
  11. someth1ng

    hsc shud i be planning for such 5 markers or just straight away write

    Generally, it's good practice to dot point a couple of keywords that you want to use because it helps keep structure in your response. This might not be an HSC answer, but this question makes me think: Highly exothermic, increase in entropy. Only reversible under specific conditions (e.g...
  12. someth1ng

    Prelim Redox Reaction question help

    A good general rule is that oxygen is almost always -2 unless it's bonded to fluorine (extremely rare).
  13. someth1ng

    Intermolecular forces HELP ASAP PLS

    In reality, polarity is a spectrum, not a binary property. It's best to consider the vectors (i.e. arrows denoting positive to negative) for each bond and consider their electronegativities. Symmetry works around a single atom but it's not good when considering a larger molecule. For example...
  14. someth1ng

    Intermolecular forces HELP ASAP PLS

    Generally, it all comes down to positive and negative charges being attracted. Dispersion forces: electron distribution fluctuates over time, so even "non-polar" compounds will have an uneven distribution of charge (but are only instantaneous). Dipole-dipole: polar compounds will have an...
  15. someth1ng

    How to compose a research question

    I really don't have a clue what you're trying to ask here because you're being quite vague. A few questions that you might want to learn about a chemical reaction can include: Can the reaction be used to create functional compounds? Are there any known examples and how is the reaction used to...
  16. someth1ng

    Can anyone quickly recap me on this

    In the case of hydrocarbons; yes, the water and organics are generally not miscible, so you get two layers and the bromine can move between the layers because it's soluble in both. Keep in mind that they could technically do the bromine water test on other samples like ethanol, and that would...
  17. someth1ng

    Heat of Combustion without moles?

    I don't think it really matters. You could get heat of combustion for each alcohol in J/g. From there, you'd try to match it with the known values J/g. There's no difference between J/g and J/mol – it's just a different measuring stick.
  18. someth1ng

    real life applications of aas

    Pharmaceuticals: impurities like heavy metals are easily detected and quantified (all impurities need to be characterized and quantified in pharma). Mining: determine metal content in ores. Water: determine metal content in drinking water (e.g. lead) Food: similar to pharmaceuticals.
  19. someth1ng

    how do I explain why ethanol is hygroscopic?

    Ethanol is polar and water is polar, so they will mix.
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