import numpy as np, matplotlib.pyplot as plt

c_h2o2 = np.array([0.02, 0.01775, 0.0158, 0.0106, 0.005])
t = np.array([0, 10, 20, 50, 100])

snitt_c = np.array([(c_h2o2[i]+c_h2o2[i-1])/2 for i in range(1,len(c_h2o2))])
snitt_t = np.array([(t[i]+t[i-1])/2 for i in range(1,len(t))])

r_liste = np.zeros(len(snitt_c))
for i in range(len(snitt_c)):
    r_liste[i] = np.polyfit([c_h2o2[i],c_h2o2[i+1]],[t[i],t[i+1]],1)[0]

plt.plot(snitt_c,-r_liste)
plt.show()