Helium Definition and 375 Threads

The density of helium gas at 0.0 degrees C is 0.179 kg/m^3. The temperature is then raised to 100.0 degrees C, but the pressure remains constant. Assuming that helium is an ideal gas, calculate the new density of the gas. Ok, so far i figure that since P is constant, I would need to work...

Would someone mind (in simple terms if possible) explaining how at the beginning of the universe Hydrogen combined to give Helium; then then how Helium combined with deuterium to create the heavier elements? I would just like to be more versed on this process... Thanks for any help!

If gravity aplies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example helium floats up to the sky? Thnx

Suppose I knew the densities of air and helium and I make a helium balloon. If I know the lift (in Newtons), how can I find the volume of the balloon?

I'm having trouble finding reliable data on the dielectric constant of helium(4) gas as a function of temperature, from 4K up. Grateful for any help

Is helium a better alternative then the current proposed fuels for fusion reactors? http://www.space.com/scienceastronomy/helium3_000630.html http://www.asi.org/adb/02/09/he3-intro.html

how come when a car accelerates w/ a helium balloon, the balloon goes forward?

Hi, It requires 79.0 eV to remove both electrons from He in the ground state. The energy to remove a single electron is 24.6 eV. What is the relationship between these two numbers? Thanks.

In a superfluid a small volume of liquid can be considered to behave as a single particle.Does this mean that ,for example,one cm^3 of helium-4 atoms has a total spin of 2?

a couple nights ago whilst my presleep thoughts wondered about, i came across a balloon filled with helium. in this thought, i saw the not uncommon sight of it floating up. then i wondered why it went up and not down or some arbitrary direction. i know helium is lighter than our oxygenic...

Stuck again with this "not so informational" astronomy book, and we need help with a question. What produced the helium in the Suns atmosphere, Jupiters atmosphere, and the suns core? :cry: can anyone help us?

No, I'm not thinking of buying one/any, but how much does one cost?, any type. Plus, how much do the two commonmost types of helium in liquid form, and/or liquid nitrogen, cost per gallon? I know liquid nitrogen is cheaper... a lot. ...If I were to not buy in bulk.

1. Calculate the rms speeds at 20 degrees celcius of atoms of helium (4u)? 2. The escapte speed from the surface of the Earth is 11.2 km/s. Find at what temp. the following gas (O2) have this value as the rms speed? 3. One mole of an ideal monatomic gas is heated from 0 degrees celcius...

Hi friends... Sometime back, I encountered the Self Consistent Field Method in Quantum Mechanics, which is used to compute wave functions in complex atoms. The book I read this from is "Practical Inorganic Chemistry" by Clyde and Day. The method is explained through an argument about the...

Given: R=8.31451 J/(K*mol) Two moles of helium gas initially at 187 K and 0.33 atm are compressed isothermally to 0.57 atm. Find the final volume of the gas. Assume the helium to behave as an ideal gas. Answer in units of m^3. I've tried this many many times and i keep getting 5.455...

sir, i get the fllowing reply for my question 'can helium be changed to hydrogen' '' Helium to Hydrogen requires energy input, for just the same reason that Hydrogen to Helium produces energy. The mass of four protons is greater than the mass of a Helium nucleus (alpha...

sir, I have to questions, 1. is it possible to change the helium of the sun to hydrogen. 2. can laser stop the electromagnetic wave if laser is charged to the electromagnetic wave face to face. soumya

I was looking at a http://chemlab.pc.maricopa.edu/periodic/isotopes.html and was wondering why the half-life was sometimes replaced with electron volts? There's an example from the table below: Helium-6 806.7 milliseconds -> Lithium-6 Helium-7 160 KEV -> Helium-6...

I can't seem to figure this simple helium balloon problem out? I would really appreciate some help? Thanks! Estimate the volume of a helium-filled balloon at STP if it is to lift a payload of 500 kg. The density of air is 1.29 kg/cubic meter and helium has a density of .178 kg/cubic meter...

This is a new launch plaform idea to assist Nasa in meeting it's extra-planetary goals. It seems that a large helium-supported platform in the upper atmosphere could save a lot of launch energy and pollution. The platform might be quite large, perhaps 0.5 to 2 km in diameter, and could be...

He I need a picture of liquid helium itself for my project on superconductors. I've looked all over but I can't find anything

The two questions that were on my exam, to be honest, i didnt answer because I didnt understand it enough to do so. But I am willing to learn and be shown the way to a legit answer, so please don't immediately give me answers. The questions are like this: The density of air near the...

Does it matter if we use one wave function to describe both electrons of a helium atom, or we need to use one wave function for each? Is there any empirical evidence of the right way?

I was wondering if any of you guys could solve this problem for me with complete solutions. I have been at it for a couple of hours and I am running out of pencil. I would really appreciate your help! Problem: A helium balloon is used to lift a load of 110 N. The weight of the balloon's...

Are there stars primarily composed of helium?