## crosssbow Group Title create a 3 by3 system of ODE IVP from this problem: Suppose three chemical species are in a process of reaction, where every minute 20% of chemical A becomes chemical B, and 25% of chemical B become chemical C. There is no supply of chemical A. The reaction stops at chemical C. At present, there are 100 grams of chemical A, 20 grams of chemical B, and no chemical C. We are interested in the First 10 minutes of the reaction. one year ago one year ago

1. UnkleRhaukus Group Title

so we need to find three equations

2. crosssbow Group Title

yes, i said x , y, and z

3. crosssbow Group Title

x=chem A y=chem B z=chem C

4. crosssbow Group Title

dx/dt=?? dy/dt=??? dz/dt=??

5. crosssbow Group Title

and i believe i know the interval [0,10]

6. crosssbow Group Title

since we are intrested in the first 10 min

7. UnkleRhaukus Group Title

so $\frac{\text dA}{\text dt}=80\%A$

8. crosssbow Group Title

why?

9. UnkleRhaukus Group Title

every minute 20% of chemical A becomes chemical B so every minute chemical A becomes 80% of was before

10. crosssbow Group Title

okay, that makes sense, how about for dB/dt?

11. UnkleRhaukus Group Title

every minute 20% of chemical A becomes chemical B, and 25% of chemical B become chemical C

12. crosssbow Group Title

20%A-25%B

13. UnkleRhaukus Group Title

and the last one/

14. crosssbow Group Title

i am not sure , maybe just 25%B??

15. crosssbow Group Title

?

16. UnkleRhaukus Group Title

i think thats right

17. crosssbow Group Title

okay thanks