I think the answer would b C
You have to use Avogadro's number (6.02x10^23 molecules/mole) to find the number of moles each reactant starts off with.
moles of Fe and O₂:
12 atoms/(6.02x10^23 atoms/mole)=1.99x10^-23 mol Fe
6 molecules/(6.02x10^23 molecules/mole)=9.967x10^-24 mol <span>O₂
</span>Then you find the limiting reagent by finding how much product each given amount of reactant can make. Which ever one produces the least amount of product is the limiting reagent.
amount of Fe₂O₃ produced:
<span>(1.99x10^-23 mol Fe)x(2mol/4mol)= 9.967x10^-24mol Fe</span>₂O₃<span>
</span>(9.967x10^-24 mol O₂)x(2mol/3mol)= 6.645x10^-24 mol Fe₂O₃<span>
</span>since oxygen produces the leas amount of product, oxygen is the limiting reagent. since we know that oxygen is the limiting reagent we can use the amount of product formed with oxygen to find the amount of iron used.
6.645x10^-24 mol Fe₂O₃x(4mol/2mol)=1.329x10^-23 mol Fe consumed
<span> find the amount left over by subtracting the original amount of Fe by the amount consumed in the reaction.
</span>1.993x10^-23-1.329x10^-23= 6.645x10^-23mol Fe left
find the number of atoms by multiplying that by Avogadro's number.
<span>(6.645x10^-23mol)x(6.02x10^23 atoms/mol)=4 atoms
</span>therefore 4 atoms of Fe will be left over after the reaction happens.
I hope this helps.
Barium forms cation : Ba²⁺
<h3>Further explanation</h3>
Given
Barium element
Required
Ion type
Solution
Barium with the symbol Ba is an alkaline earth metal element having the atomic number 56
Electron configuration of Barium: [Xe] 6s2
If we look at this configuration, then Barium will try to achieve stability by removing 2 electrons so that the electron configuration is the same as the noble gas Xenon (Xe)
Because it removes 2 electrons, Barium has the number of protons> the number of electrons so that the charge is positive and forms a cation
Answer:
C
Explanation:
C is the best answer. The endocrine system releases and controls hormones, which are basically just signals sent through the body.
These hormones regulate homeostasis, which is how your body stays at regular levels / stays the same. It keeps your body at steady conditions.
The two angles would be both 41 degrees.

x in this case would be 14 degrees.