Construct a calibration curve: (a) Subtract the blank value (9.1) from all other values (this means that your first data point will be 0,0). Then use the LINEST calculation of least squares to find the slope and intercept and their uncertainties. slope 869 intercept (b) Replicate measurements of an unknown gave 152.1, 152.4, 153.9, and 152.7 mV, and a blank gave 9.1, 9.4, 10.6, and 9.0 mV. Subtract the average blank from the average unknown to find the average corrected signal for the unknown. 143.25 Check the number of significant figures. (c) Find the concentration of the unknown and its uncertainty.

Many common materials that we ingest, though quite safe in reasonable quantities, become toxic when taken in very large doses. A measure of toxicity is the LD50 value (Lethal Dose, 50%). It is the quantity of material, expressed in mg of material per kg of subject-body-weight that, if administered to a population of subjects, would cause 50% of the population to die. The LD50 value for FD&C Red Dye No. 40 is >10,000 mg/kg in rats. Assume that the LD50 value for humans is the same as for rats. Calculate the number of mg of Allura Red present in an 8 fluid ounce glass of the beverage you used in this lab. Assume that the concentration of Allura Red in the beverage is 0.000054 M. The molar mass of Allura Red is 496.42 grams/mol 1 fl oz = 29.5735 mL Do not include units with your answer.

Assuming that you weighted a piece of silver five times and each time you got 52 grams. However, the actual weight from the Bureau of Standards said it should weigh 50 g. (a) What is the % relative errors? (b) What type of error does this exemplify? (c) Does this affect (a) reliability (b) Accuracy (c) both a & b

1) Report the results of this calculation along with both the percent relative and absolute uncertainties. 417.3 ± 0.4 × 71.8 ± 0.7(647.21 ± 0.2 − 182.3 ± 0.4) Absolute uncertainty:Percent uncertainty:

Part C F10 BO O 3.04 × 10³ 6.27 x 10-1 The dosage of quinine when a 145-lb adult takes a 200.-mg tablet is equivalent to ug drug per kg of body weight. ► View Available Hint(s) O 627 O 1.38 × 10³ P Pearson * Education Inc. All rights reserved. | Terms of Use Privacy Policy. Permissions Contact Us | Bb Home L End Insert ■ Review |- Constants | Periodic Table 1 2

A CHM 126 student weighed an empty and clean 50-mL flask. The studernt then used a 10-ml volumetric pipet to transfer deionized water into the flask. Afterwards, she re-weighed the flask with the water. Using her resulting data and the density of water, she determined her measured volume of water in units of mL. Her data is listed below. What was the percent error in her measured milliliters of water? As always, be sure to report your answer with the proper number of significant figures while using proper rounding. mass of empty flask = 62.258 g mass of flask with water = 72.118 g density of water = 0.99821 g/mL Type your answer in the space below without the units.