Yeast contains the enzyme catalase, which breaks down hydrogen peroxide into oxygen and water.
A student added yeast suspension to a solution of hydrogen peroxide and collected the oxygen given off by the reaction. The results are shown in the graph below, where a dashed tangent line is drawn at t=40 st = 40\text{ s}t=40 s.
Which of the following shows the rate of reaction at 40 s?
0.45 cm3 s−10.45\text{ cm}^3\text{ s}^{-1}0.45 cm3 s−1
0.90 cm3 s−10.90\text{ cm}^3\text{ s}^{-1}0.90 cm3 s−1
1.38 cm3 s−11.38\text{ cm}^3\text{ s}^{-1}1.38 cm3 s−1
1.80 cm3 s−11.80\text{ cm}^3\text{ s}^{-1}1.80 cm3 s−1
