Recent content by sveioen

When I look up Snell's law on Wikipedia it says \frac{\sin \theta_1}{\sin \theta_2}=\frac{v_1}{v_2}=\frac{n_2}{n_1} Why does the subscript change in the n_n ? Isnt v_1=n_1 and v_2=n_2? Thanks for answering

Homework Statement Given a three layer model ------------------------------------------------- v_1=1.5km/s ------------------------------------------------- v_2=1.3km/s ------------------------------------------------- v_3=2.0km/s Assume a ray goes through layer 1 and hits the interface...

Ok, I did, and I ended up with getting atoms/second, which I guess is..right?

Excellent! So, I got 1,9804\times 10^{-9}\mbox{ moles/second}. So the amount of Na and Cl that crystallizes each second would be 6,0221415\times 10^{23}\times 1,9804\times 10^{-9}=1,1926\times 10^{15}. I guess that since the mole ratio is 1:1, Na^{+}=\frac{1,1926\times 10^{15}}{2}\mbox{, }...

Ok, so I have MM_{NaCl}=58.44277 \text{g/mol}, and I guess I have will have to find the amount of moles; n=\frac{30\times 10^{-3}}{58.44277}=5,1332\times 10^{-4}. So far so good? Would the next thing be to do \frac{5,1332\times 10^{-4}}{3*24*60^2}, to get the number of moles crystallized per second?

If a salt crystal forms after 3 days of evaporation, and the crystal mass is 30 mg, how many Na+ and Cl- ions was added to the crystal each second (average). How do I solve this?

Could anyone please help me with this? I don't have a clue where to begin. :frown:

Wow, so it is that easy. Thank you very much gravenewworld!:smile:

[SOLVED] Removing Pb from water Could anyone get me going with this?

Having a day at the lab tomorrow, and one of the pre-lab-questions is Anyone got a clue about this one?

Nope don't have answer (yet) :(, but it seems kinda right.. Probably is equilibrum concentration..

I got 2,21 \times 10^{-7}, which seems reasonable I guess. Maybe a bit low?!

Ok, so pOH = 14 - pH = 14 - 8,3 = 5,7. Concentration of OH- and NH4 is therefore 1,995 \times 10^{-6}? And then [NH3] = \frac{[OH^-][NH4^+]}{K_b}?

Hello all, I had chemistry a long time ago, but now I am very rusty at it :frown: so I am hoping you can get me started with this problem I have; A particular solution of ammonia (Kb = 1.8 x 10-5) has a pH of 8.3. What is the concentration of ammonia in this solution? Is it the...