1.1. In the Haber process, nitrogen and hydrogen are reacted together in conditions of high pressure and temperature to produce ammonia. 

The equation for the reaction is as follows: 

N₂ + 3H₂ → 2NH₃  

Calculate the percentage atom economy for the production of ammonia.

Relative formula masses (M_r):  N₂ = 28;  H₂ = 2;  NH₃= 17

Percentage atom economy = ____________________ %

1.2. Figure 1 shows how the percentage yield of ammonia varies with changing conditions of pressure.

Figure 1

Describe the trend shown in Figure 1.

1.3. Use Figure 1 to determine the difference in percentage yield at 100 atmospheres pressure and at 250 atmospheres pressure.

Difference % yield NH₃ = ________ %