Answer:
Inert gases
Explanation:
Inert elements have a stable electron configuration meaning their shells/orbitals are full with their requisite number of electrons. Therefore, gaining or losing an electron would take high ionization energy. Therefore they are less likely to be involved in chemical reaction unless a high amount of energy is used. An example of an inert gas is Helium.
1) Write the balaced chemical equation:
H2 + 2O2 → 2H2O
2) Infere the molar ratios:
1 mol H2 : 2 mol of water
3) Make the calculus as the direct proportion relation:
[2 mol H2O] / [1 mol H2] * 7 mol H2 = 14 mol H2
As you see you produce the double number of moles of H2O than number of moles of H2 used.
Answer: 14 moles
Answer:

Explanation:
Hello!
In this case, since 12.75 g of calcium iodide has the following number of moles (molar mass = 293.89 g/mol):

In such a way, since 1 mole of calcium iodide contains 2 moles of atoms of iodine, and one mole of atoms of iodine contains 6.022x10²³ atoms (Avogadro's number), we compute the resulting atoms as shown below:

Best regards!
Down...
and if you were wondering, the earth pushes back
Unsaturation (IHD) 2 hydrogen Needed
IHD = [(2n+2) -H]/2
(H: X=1, N=-1, O= zero)
Unsaturation:
Double bonds = 1
Rings = 1
Triple Bonds = 2
The degrees of unsaturation in a molecule are additive — a
molecule with one double bond has one degree of unsaturation, a molecule with
two double bonds has two degrees of unsaturation, and so forth.