The given question is incomplete. the complete question is:
The world burns the fossil fuel equivalent of approximately
kg of petroleum per year. Assume that all of this petroleum is in the form of octane. Calculate how much CO2 in kilograms is produced by world fossil fuel combustion per year.( Hint: Begin by writing a balanced equation for the combustion of octane.)
Answer: 
Explanation:
Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

To calculate the moles :

According to stoichiometry :
As 2 moles of octane give = 16 moles of 
Thus
of octane give =
of 
Mass of 
Thus
of
is produced by world fossil fuel combustion per year.
You have 3.498 moles of the gas/neon
Answer:
moles of calcium hydroxide= 21.75 mol
a) 43.5 mol
b) 7.25 mol
Explanation:
Please see the attached picture for the full solution.
Answer : The concentration of
is, 
Explanation :
When we assume this reaction is driven to completion because of the large excess of one ion then we are assuming limiting reagent is
and
is excess reagent.
First we have to calculate the moles of KSCN.


Moles of KSCN = Moles of
= Moles of
= 
Now we have to calculate the concentration of ![[Fe(SCN)]^{2+}](https://tex.z-dn.net/?f=%5BFe%28SCN%29%5D%5E%7B2%2B%7D)
![\text{Concentration of }[Fe(SCN)]^{2+}=\frac{\text{Moles of }[Fe(SCN)]^{2+}}{\text{Volume of solution}}](https://tex.z-dn.net/?f=%5Ctext%7BConcentration%20of%20%7D%5BFe%28SCN%29%5D%5E%7B2%2B%7D%3D%5Cfrac%7B%5Ctext%7BMoles%20of%20%7D%5BFe%28SCN%29%5D%5E%7B2%2B%7D%7D%7B%5Ctext%7BVolume%20of%20solution%7D%7D)
Total volume of solution = (6.00 + 5.00 + 14.00) = 25.00 mL = 0.025 L
![\text{Concentration of }[Fe(SCN)]^{2+}=\frac{1.08\times 10^{-5}mol}{0.025L}=4.32\times 10^{-4}M](https://tex.z-dn.net/?f=%5Ctext%7BConcentration%20of%20%7D%5BFe%28SCN%29%5D%5E%7B2%2B%7D%3D%5Cfrac%7B1.08%5Ctimes%2010%5E%7B-5%7Dmol%7D%7B0.025L%7D%3D4.32%5Ctimes%2010%5E%7B-4%7DM)
Thus, the concentration of
is, 
Answer:
Potential energy
Explanation:
The thrown baseball is converting from kinetic energy into potential energy. When it finally stops at a particular height, it attains its maximum potential energy at the position or point.
- Potential energy is the energy at rest of body.
- Kinetic energy is the energy due to the motion of body.
The more a body speeds, the higher its kinetic energy attained.
As a body comes to rest, at a height, it attains potential energy.
The body during flight decreases in kinetic energy but increases its potential energy due to gravity pulling it to rest.