In 1909 Fritz Haber discovered the workable conditions under which nitrogen, N2(g), and hydrogen, H2(g), would combine using to produce ammonia. The conditions included medium temperature (~500oC), very high pressure (~351kPa), and an iron catalyst. The reaction is represented by the equation:
N2(g) + 3H2(g) → 2NH3(g)
How many grams of nitrogen are needed to produce 100 grams of ammonia gas?

A) 28.0g N2
B) 50.0g N2
C) 56.0g 2
D) 82.4g N2

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later