Consider the following reaction: a. how much heat is evolved for the production of 1.00 mol of h2o(l)? b. how much heat is evolved when 4.03 g of hydrogen is reacted with excess oxygen? c. how much heat is evolved when 186 g of oxygen is reacted wih excess hydrogen? d. the total volume of hydrogen gas needed to fill the hindenburg was 2.0 108 l at 1.0 atm and 25c. how much heat was evolved when the hindenburg exploded, assuming all

Explanation:

A.  The information provided tells you that 572 J is evolved in the production of TWO moles H2O.  So, you should be able to figure out the heat evolved in the production of ONE mole H2O.

B.  How many moles of O2 is 186 g of O2?  186 g x 1 mol/32 g = 5.81 moles.  From the equation, you know that 1 mole O2 generates 572 J of heat.  So heat evolved from 5.81 moles is 5.81 x this amount.

C.  How much heat is reacted?  You probably mean how much heat is evolved.  How many moles of H2 is 4.03 g of H2?

4.03 g H2 x 1 mole/2 g = 2.015 moles H2.  TWO moles H2 generates 572 J of heat, so how much is generated by 2.015 moles H2?  Just multiply.