Trans fats: think about how the prefix trans- is used in naming alkenes.

Alkenes have done bonds and they have two geometrical isomer: cis and trans alkene.  

In cis alkenes identical atoms or groups are positioned on same side of the double bond and in trans alkenes identical atoms or groups are positioned on opposite side of the double bond.  

Unsaturated fatty acids have both cis and trans fats. Elaidic acid is an example of trans found in hydrogenated vegetable oil.  

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.

c) should be the answer.