-1
votes
0answers
19 views

Thermodynamics Assignment: Combustion [on hold]

Acetylene, Methane and Octane are burnt in air (75% Nitrogen, 25% Oxygen) and forms Carbon Dioxide, Carbon Monoxide, Nitrogen and Water This is the unbalanced equation: C2H2 + CH4 + C8H18 + O2 + N2 ...
1
vote
0answers
15 views

Calculate Avogadro's constant based on grating constant and density of NaCl crystal [closed]

The tittle says it all. I need to calculate Avogadro's constant based on grating constant of NaCl crystal ( in this case 278 micrometers ) and crystal density ( 2.1 grams per cubic centimeter ).
0
votes
1answer
60 views

Calculate the required water for humidity [closed]

I'm not sure if this is the right place to ask. I have a humidifier, and a closed room. Basically, I want to know the required water to reach a certain level of humidity. My room volume is 42 meter ...
-3
votes
1answer
97 views

How fast will I get if I burn a comet? [closed]

Assuming I have a spacecraft which is $30,000\,\mathrm{kg}$ (roughly the size of the Apollo spacecraft). If I take a comet and (theoretically) electrolize it perfectly to hydrogen and oxygen. I know ...
0
votes
2answers
2k views

How does one calculate the volume of a nucleus and the volume of an atom (in this case hydrogen)?

The hydrogen atom contains 1 proton and 1 electron. The radius of the proton is approximately 1.0 fm (femtometers), and the radius of the hydrogen atom is approximately 53 pm (picometers).
2
votes
1answer
218 views

Electric dipole transitions/expectation value of position

Part of a homework question asks to show that for $\ell=0$ in both $\Psi_i$ and $\Psi_f$, we have $$ \int \Psi_i^\ast \vec{r} \Psi_f \; d\tau = 0 $$ for the position vector $\vec{r}$. (This is for ...
4
votes
1answer
238 views

Voltage drop over a cell membrane

Again, a problem from exam preparation: [A] cell's membrane allows sodium ions to pass through it, but not chlorine ions. The cell is placed in a salty solution with a ten times higher ...