Passage I
When a substance dissolves in H2O, heat is either absorbed from or given off to the solution. “Experiments were done in which a known mass of a solute was added to a known mass of H2O at a known initial temperature (Ti) in a closed, insulated container. When the maximum 'temperature change of the solution had occurred, the final temperature (Tf) was recorded. The maximum temperature change (△T) was then calculated as follows:
△T = Tf - Ti
Figures 1 and 2 show the results for lithium chloride (LiCl) and ammonium nitrate (NH4NO3), respectively. In each trial, all of the solute completely dissolved.
2. Consider the trials represented in Figure 1 involving 20 g of LiCl. From trial to trial, as the LiCl concentration in the resulting solutions increased, the △T that was observed:
Your Answer is
Correct Answer is F
Explanation
Looking at figure 1, it can be found that as the amount of mass of LiCl in the abscissa gradually increases, the ordinate ΔT of several lines increases, so it is increase only