The elements hydrogen and helium are exempted from the octet rule. The octet rule, as you might recall, states that elements prefer to have eight electrons in their valence shells. Hydrogen has a lone electron in its valence shell, and cannot begin to "borrow" electrons to create a shell with eight electrons in it. Remember that its electron, a 1s1 electron, is in the 1s shell. Helium has a full 1s shell with its two electrons (1s1, 1s2). It has no interest in any other electron configuration because its valence shell is full. The first two elements on the Periodic Table are the exceptions to the octet rule. A link can be found below.
Hydrogen and helium are formed in Sun.
The result of this separation will be pure hydrogen and pure helium.
About 96% hydrogen and 2% helium.
No. helium does not react with any element.
Helium, hydrogen, and air are gases.
Hydrogen and helium
\helium (He) and hydrogen (H)
The chemical symbol for helium is "He."
Hydrogen is H2. Helium is He.
Hydrogen and helium are the two most abundant elements in the universe.
Hydrogen, helium and the transition metals
Hydrogen and helium are formed in Sun.
Hydrogen is lighter than Helium.
mostly hydrogen and helium
No. Helium and Hydrogen are two different elements.
Hydrogen and helium. Mostly hydrogen.
No, helium is almost 4 times as heavy as hydrogen.