# Recent content by BogMonkey

1. ### Diverging lenses + mirrors

I noticed that for converging devices the size and orientation of the image formed depends on whether the object is located inside or outside the focal point and center of curvature. I also read that no matter where the object is with respect to a diverging lense the image formed will always be...
2. ### Trajectory of charged particle moving in a magnetic field

Ah right that explains it. Thanks a lot.
3. ### Trajectory of charged particle moving in a magnetic field

Damn I meant to say pink lines in the diagram not green lines. What I was really asking is if the pink lines are the magnetic field lines. I see that the green circular lines are the trajectory of the particle but I'm wondering if the particles initial velocity upon entering the magnetic field...
4. ### Trajectory of charged particle moving in a magnetic field

In this video here are those pink green the magnetic field lines? If so where does the proton come from? If I'm not mistaken a charged particle in motion will only be influenced by the magnetic field if its not moving parallel to the magnetic field lines but in this video the proton appears to...
5. ### Rectifying an conventional error

Rectifying an "conventional error" In textbooks I always see "by convention it is said to flow from positive to negative but in reality its from negative to positive" and this is why I always end up explaining that when I get asked a question about how current works or how batteries work on a...
6. ### Calculating pKa when pH is known

I started this thread a while ago but never figured it out in the end can someone tell me if my idea of this is correct or not. Lets say I add 2 moles of a weak acid acetic acid to a liter of water (at STP). If I'm not mistaken the acetic acid will dissociate slightly depending on its...
7. ### The strength of strong acids

Sulphuric acid is a diprotic acid that dissociates completely when dissolved in water. How does a monoprotic acid like trifluoromethanesulfonic acid produce a greater pH change than H2SO4?
8. ### Calculating pKa when pH is known

I submitted that assignment already I'm not asking for help with that question I'm trying to learn the concept. If I add 15 tons of pure NaOH to a 10 litre bucket of 0.0005M CH3COOH solution theres no way the amount of acetate ions present is going to equal the god knows how many moles of NaOH...
9. ### Calculating pKa when pH is known

All I know is that acetic acid is a weak acid and it doesn't dissociate fully into acetate and H+ ions when dissolved. I know KOH is a strong acid. All the charged species are K+ and H+ cations as well as OH- and CH3COO- anions. I know exactly how many K+ ions are present and ignoring the...
10. ### Motivation for learning maths

Thanks a lot! What you said "being able to come up with methods to link the variables in an unknown problem together" got me thinking. The only 3 variables I've thought about are acceleration, velocity and displacement but there are probably plenty of these variables within variables that I'll...
11. ### Calculating pKa when pH is known

Heres my calculation The real pKa of acetic acid is around 4.7 so I wasn't too far off. I still don't know why the acetate ions are equal to the KOH though. If I react some acetic acid with KOH is it only the dissociated acetate ions that are involved in the reaction?
12. ### Motivation for learning maths

I usually have no shortage of motivation because I like to think about all the practical applications that I could use this theory for in my future endeavours and also how the theory I'm learning expands on and fills in the gaps of what I already know. In maths I can't automatically think of...
13. ### Calculating pKa when pH is known

Heres a question involving what I'm talking about When 5mls of 0.05M CH3COOH is allowed to react with 1.5mls of 0.05M KOH. The pH is found to be 4.43. Using the Henderson-Hasselback equation calculate the pKa. My teacher told me that you can find the amount of dissociated ions of the...

Thanks.
15. ### Calibration Curves

I looked this up but couldn't find sufficient information on it. What I know is that calibration curves are used to find the concentration of an unknown compound by graphing a series of measurements of a property like light absorbance from standard solutions of that compound. What I don't get is...