Answer:
0.87mole
Explanation:
The reaction equation is given as;
4Fe + 3O₂ → 2Fe₂O₃
Number of moles of Fe₂O₃ in 138.5g
To solve this problem;
Number of moles = 
Molar mass of Fe₂O₃ = 2(56) + 3(16) = 160g/mol
Now;
Number of moles = 
= 0.87mole
Aluminum is the correct answer
They gain energy , it also allows plants to create organic molecules that they use as fuel.
In order to find the number of moles with a given mass of Helium, we need to use its molar mass, which is 4.0026g/mol, therefore we will have:
4.0026g = 1 mol of Helium
91.5g = x moles of Helium
x = 22.86 moles of Helium in 91.5 grams
Nonpolar covalent bonds are chemical bonds where two atoms share a pair of electrons with each other and the electronegativities of the two atoms are equal. An example is methane. It has four carbon-hydrogen single covalent bonds. These bonds are nonpolar because the electrons are shared equally.
