How was helium first discovered?

mining of the radioactive element uranium
using spectral analysis of the suns’ emission spectra
hubble obtaining samples from explosions off the surface of the sun
deep sea mining off the coast of texas

the answer is true.

this statement is true.

The density of water is 1 g/cm cubed and in order for the pebble to sink its density has to be greater than the density of water and in order for the twig to float its density has to be less than the density of water

Pcl5 + 4 h2o = h3po4 + 5 hclthe ratio is 1: 5 for  pcl  and hcl, 1 mole of pcl produces 5 moles of hclmolecular weight of pcl5 is: 31 + (5 x 35.5) = 208.5above we have 75.5 / 208.5 = 0.36 moles so this will produce0.36 x 5 = 1.81 moles of hcl.

I’m pretty sure it’s filtration