I need some help with this question. I\'m not understanding what average should

Question

I need some help with this question. I'm not understanding what average should I calculate. Also, which full set of sample calculation should I provide?

1. Based on your data, determine an average value for the concentration of the stock NaOH solution. Indicate which data points you have included in your determination (you should use at least three), and provide a full set of sample calculations for one of your trials. Table 1: Standardization of a sodium hydroxide solution NaOH sample code Indicator used

Explanation / Answer

I did this experiment a few years ago. Here is what I know:

To calculate the concentration of NaOH, you need to use the following formula:

M of NaOH = (mass of KHP used) / [(volume of NaOH used) (MW of KHP)]

Using the above formula for each of the samples, we get the following concentrations:

Trial 1 = 0.4005 g / [(0.018 L) (204.23 g / mol)] = 0.1089 M (to four sig. figs.)

Trial 2 = 0.4144 g / [(0.01856 L) (204.23 g / mol)] = 0.1093 M (to four sig. figs.)

Trial 3 = 0.4184 g / [(0.01879 L) (204.23 g / mol)] = 0.1090 M (to four sig. figs.)

Trial 4 = 0.4235 g / [(0.019 L) (204.23 g / mol)] = 0.1091 M (to four sig. figs.)

Now, calculating the average concentration of NaOH from the 4 trials:

(0.1089 + 0.1093 + 0.1090 + 0.1091) / 4 = 0.1091 M

Keep in mind the equation for this titration is as follows:

OH^-(aq) + HP^-(aq) = H2O(l) + P^2-(aq)

Hope that helps! :)

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---