Problem 3
what quantity of heat is associated with the synthesis of 45.0 g of nh3 according to the following equation?
4 no(g) + 6 h2o(l) > 4 nh3(g) + 5 o2(9) ah = +1170 kj

774.265 kJ

Explanation:

Given an endothermic reaction in which 4 moles of production of ammonia requires 1170 kJ amount of energy . each mole of ammonia corresponds to 17grams. which means that 68 grams of ammonia production requires 1170 kJ amount of energy .

we are asked to find out the heat energy assosiated with the production of 45gms of ammonia  let us calculate the heat energy assosiated with per gram production of ammonia that is one gram of ammonia synthesis reqires amount of energy .Then 45 gms require amount of energy which is equal to 774.265kJ

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles