60 elements! I don't exactly know every element known, so if you are asking that, please tell us, but what I do know is that there were 60 elements in the periodic table by 1860.
One molecule of water contains two atoms of hydrogen and one atom of oxygen, the atomicity of water is three.
H = planks constant
<span>m = mass of the object </span>
<span>u = velocity of the object </span>
<span>h = 6.626 * 10^-34 J/s </span>
<span>the mass of an electron is 9.12*10^-31 kg </span>
<span>10% speed of light = 10% * 3*10^8 = 3*10^7 m/s, i dont have my graphing calc with me right now so i leave the technicalities up to you </span>