Which of the following solutions has the greater buffer capacity: 100 mL of 0.30 M HNO2-0.30 M NaNO2 or 100 mL of 0.10 M HNO2-0.10 M NaNO2? Explain.

Video transcript

hi everyone for this problem it reads identify which of the following two solutions has a higher buffer capacity. So let's go ahead and define what higher buffer capacity means. A buffer has the highest buffer capacity. When the ratio of conjugate base to weak acid is equal to one. So we're looking at the concentration of conjugate base too weak acid. And since the two buffers have equal volumes and identical mill arat ease, well, just look at the conjugate base to weak acid ratios for both. So let's go ahead and start with a. Okay, so for a we're looking at the concentration of conjugate base too weak acid and when we do this we see that the concentration of conjugate base is 0.15 molar and the concentration of weak acid is 0.15 molar. So the ratio here is one and first solution be our concentration of conjugate base over concentration of weak acid. For the conjugate base it is 0.15 Molar. And for the weak acid it is 0.10 Molar. So then this ratio is 1.5. Since the buffer since the first buffer, which is solution a has a ratio equal to one, it's going to have the higher buffer capacity. Okay, so we're gonna go ahead and highlight a as our correct answer here. And the reasoning is because the well right here so when it's equal to one this is the highest buffer capacity, that is it for this problem. I hope this was helpful