Find the number of moles of water that can be formed if you have 178 mol of hydrogen gas and 84 mol of oxygen gas. give an explanation why.

-  168 moles of water are formed.

Solution:- The balanced equation for the formation of water from hydrogen and oxygen gases is:

From this equation hydrogen and oxygen react in 2:1 mol ratio.

We have been given with 178 moles of hydrogen and 84 moles of oxygen. We need to figure out the limiting reactant first. For this let's either calculate the moles of oxygen required to react completely with 178 moles of hydrogen or the moles of hydrogen required to react completely with 84 moles of oxygen.

Let's say we calculate the moles of oxygen required to react completely with 178 moles of hydrogen:

=

From the above calculations, 89 moles of oxygen are required to react completely with 178 moles of hydrogen but only 84 moles of oxygen are available, It means oxygen is the limiting reactant and the product yield depends on it.

There is 1:2 mol ratio between oxygen and water. Let's calculate the moles of water for given 84 moles of oxygen:

=

So, the reaction of 178 moles of hydrogen and 84 moles of oxygen gives 168 moles of water.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.