What is the final chemical equation from the following intermediate chemical equations?

the answer to that question is a

Answer : The correct option is, (1)

Explanation :

The two intermediate chemical equations are :

    ..............(1)

   .............(2)

Now adding equation (1) and equation (2), we get

Now we will cancel the from both the sides of the equation, we get

Now we will subtracting from the , we get

This is the final chemical equation.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2