Chemical reaction, generally speaking. It's a vague definition, but it's easy to remember.
You should clean up after every investigation because if you leave a mess, maybe another detective will come in and get lost because of the mess you left.
Use a strip of paper covered in PH indicating dye.
The answer would be modeling, because craving is when you take a block of something and slice it t make something,and casting is when you put layers over layers to form a something. so the answer will be modeling.
![\\ \tt\leadsto \dfrac{d[NH_3]}{dt}=1.50\times 10^{-6}](https://tex.z-dn.net/?f=%5C%5C%20%5Ctt%5Cleadsto%20%5Cdfrac%7Bd%5BNH_3%5D%7D%7Bdt%7D%3D1.50%5Ctimes%2010%5E%7B-6%7D)
- dt remains same for reaction
![\\ \tt\leadsto \dfrac{d[H_2]}{dt}=\dfrac{3}{2}\dfrac{d[NH_3]}{dt}](https://tex.z-dn.net/?f=%5C%5C%20%5Ctt%5Cleadsto%20%5Cdfrac%7Bd%5BH_2%5D%7D%7Bdt%7D%3D%5Cdfrac%7B3%7D%7B2%7D%5Cdfrac%7Bd%5BNH_3%5D%7D%7Bdt%7D)
![\\ \tt\leadsto \dfrac{d[H_2]}{dt}=\dfrac{3}{2}(1.5\times 10^{-6})](https://tex.z-dn.net/?f=%5C%5C%20%5Ctt%5Cleadsto%20%5Cdfrac%7Bd%5BH_2%5D%7D%7Bdt%7D%3D%5Cdfrac%7B3%7D%7B2%7D%281.5%5Ctimes%2010%5E%7B-6%7D%29)
![\\ \tt\leadsto \dfrac{d[H_2]}{dt}=2.25\times 10^{-6}Ms^{-1}](https://tex.z-dn.net/?f=%5C%5C%20%5Ctt%5Cleadsto%20%5Cdfrac%7Bd%5BH_2%5D%7D%7Bdt%7D%3D2.25%5Ctimes%2010%5E%7B-6%7DMs%5E%7B-1%7D)
M is molarity here not metre