Which of the indicators given in Figure 16.5, methyl violet, bromcresol green, phenol red, or thymolphthalein, would be most appropriate to detect a pH change from: (c) 2 to 0?

Video transcript

Hi everyone for this problem. It reads a certain liquid has been analyzed and demonstrated a ph change from 6 to 8, choose the most appropriate indicator to detect this ph change based on the figure below. So we want to choose the indicator that's going to show a ph change from 6 to 8 and were given four indicators here. So let's take a look at our four indicators and estimate the range for each. Okay, so for our first indicator we can estimate this range to be eight a ph of eight to about nine point nine. For our second indicator, we can estimate this range to be six to about 8.1. For our third indicator will estimate this ph range to be from 6 to 7.6 and for our last indicator will estimate this to be from about 5-6.7. So we want to choose the indicator that demonstrates a change from 6-8. So our first indicator does not indicate that. Our second indicator does not indicate that because it goes above eight. Our third indicator is between that or does demonstrate that range from 6 to 7.6. And our last indicator does not demonstrate that range. So we can go ahead and say that our third indicator, bromo time, all blue is going to be the most appropriate indicator to detect this ph change based on this figure. That is it for this problem. I hope this was helpful