Final answer:
To find out the mass of nitrogen that reacted to form 1.26 grams of ammonia, we subtract 0.55 grams of hydrogen from the mass of ammonia, which gives us 0.71 grams of nitrogen.
Step-by-step explanation:
If 0.55 grams of hydrogen reacts with nitrogen to form 1.26 grams of ammonia (NH3), to find out how many grams of nitrogen reacted, we need to consider the mass of ammonia produced and subtract the mass of hydrogen that reacted, since the mass of ammonia is the sum of the masses of hydrogen and nitrogen that reacted. We have:
- Mass of ammonia (NH3) = 1.26 g
- Mass of hydrogen (H2) that reacted = 0.55 g
- Mass of nitrogen (N2) that reacted = Mass of ammonia - Mass of hydrogen
So, the mass of nitrogen that reacted is:
1.26 g (NH3) - 0.55 g (H2) = 0.71 g (N2)
Therefore, the correct answer is a) 0.71 grams.