Passage V

Students studied the photodecomposition (breakdown by light) of p-nitrophenol (a toxic pollutant) in wastewater. They measured the concentration of p-nitrophenol (in parts per million, ppm) in wastewater samples during exposure to various lighting conditions. Titanium dioxide (TiO2) and/or hydrogen peroxide (H2O2) were added to some samples at the start of exposure (time = 0 min). TiO2 and H2O2 speed up some photodecomposition reactions. The results of 3 sets of experiments are shown in Figures 1-3.

26. Based on the information in the passage, which of the following best describes and explains the results shown in Figure 2? As time increased from 0 min to 180 min, the concentration of p-nitrophenol in the 3 samples:

Answer and Explanation

Your Answer is

Correct Answer is G

Explanation

Looking at figure 2, as the abscissa increases, the ordinate decreases, so choose decrease to exclude H & J;

According to the photodecomposition of the first line of the first paragraph of the article, the Knowing that p-nitrophenol is decomposed, so choose G