PHYS_102_lab_5

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We are stuck on 9.  We get how Q is 16 and rxn goes left.   at eq 2+ x.    2 + x.    -2 x We get x= 1.    Therefore  k = 4.  Please help us.   Questin 9.  See conditions from 8 This is not a graded question as it is a practice question . I am 60 years old and helping my son prepare for the AP exam in a few months. We do questions at the back of the textbook by Zumdahl and Zumdahl

True or false and why is false 1   There are 2 major classes of keratins: alpha keratins (found in mammals) and beta keratins (found in feathers and scales of birds and reptiles) 2  One estimate of mobility within a crystal is the B-factor that reflects spreading or blurring of electron density   3 In NMR, the longitudinal relaxation time (T1) reflects the rate at which magnetization returns to the longitudinal axis after a pulse

H J K L Enter V B N M Shift Chapter 2 An Introduction to the Chemistry of Life 37 SELF-QUIZ: TESTING YOUR KNOWLEDGE 1. Each atom has a nucleus made up of р. 24. 2. In atoms, the number of protons is usually equal to the number of 3. The atomic number of an atom is equal to the number of 7. Proteins and carbohydrates consist primarily of carbon, hydrogen, and oxygen; these two molecules are types of and neutrons. -compounds. p. 31. 8. On the pH scale, a pH of is neutral; a solution with a pH less than this is this is 9. Chemicals like bicarbonate that resist pH change are called р. 25. and a solution with a pH greater than р. 32, in the nucleus. p. 26. 4 An alternative form of an atom is called an differs in the number of neutrons in the nucleus. p. 26. 5. A bond formed between two atoms that share electrons is called it p. 33. 10. When water molecules dissociate, they form and ions. p. 32. bond. p. 28. bonds form between oppositely charged atoms of a(n) polar covalent bonds of…

If the standard addition intercept is the major source of uncertainty, find the uncertainty in the concentration of Sr in tooth enamel in parts per million. Find the 95% confidence interval for Sr in tooth enamel.

one: Topic Molecular Spectroscopy (16 marks) You were given an unknown mixture that contains two metal salts (A) Co(NO3)2 and (B) Cr(NO3)2 and requested to determine their concentration. The following representative information about the absorbance data were also provided. Measurements were made in a 1.0 cm quartz cells. Pure A (mol/l) Pure B (mol/l) 0 Abs @510 nm Abs @575 nm 1.5 x 101 0 6 x 102 Unknown conc in mixture 0.714 0.097 0.298 0.757 Unknown conc in mixture 0.671 0.330 How would you go about calculating the concentration of the two salts?

The quenching of tryptophan fluorescence by dissolved O₂ gas was monitored by measuring the emission lifetimes at 348 nm in aqueous solutions. [0₂]/(10-² mol dm-³) T/(10-⁹ s) 0 2.3 5.5 8 10.8 2.6 1.5 0.92 0.71 0.57 A. 0.95 E-2 M B. 4.3 E-2 M C. 1.8 E-2 M D. 3.0 E-2 M E. None of the choices From the data above, predict the value of [0₂] required to decrease the intensity of tryptophan emission to 50% of the unquenched value.

Given the following size frequency for a dust: Size Interval (um) 7-17.5 17.5-21 21-25 25-28 28-30 30-33 33-36 36-41 41-49 49-70 % by Number 10 10 10 10 10 10 10 10 10 10 a. Plot the cumulative frequency distributions (in %) of the number, surface area, and mass on linear graph paper assuming all particles are spheres with Pp 1.6 g cm ³. = b. Is this a log-normally distributed dust?

what is the concentration of the unknown sample using serial diluitions: 0.05M 1.7472nm, 0.025M 0.8569nm, 0.0125M 0.4167nm, 0.00625M 0.1958nm the epsilon value is 0.0101 and l is 1 cm

Just part b!!!

Consider the reaction : A+B 2 AB. A calibration plot was constructed using x as the concentration for AB in M and y as the absorbance value of AB, it provided the linear equation : y=25x+0.0008. Determine the concentration of AB in M if the absorbance value is 1.22. Round and report your value to the THIRD decimal place. Numeric value only, no unit. No new data to sa IMG 0915.jpeg e to search PrtScn Home

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How to calculate the concentration of the two salts?

For the prelab today, all solutions were made using the procedure as outlined in your lab manual. When the absorbances of the solutions were measured, the following data were collected: Part 1 Part 2 Solution Absorbance Solution Absorbance 1 0.000 1 0.000 2 0.300 2 0.343 0.450 0.498 4 0.600 0.642 0.750 5 0.777 Use the data given above to calculate the average value of K for the equilibrium: Fe* (aq) + SCN' (aq) - Fe(SCN)2*(aq) Average K = 3. 4- 3.

SPECTROPHOTOMETRY Two groups in a BIO 120 lab extracted a blue-violet pigment from mayana plant which was to be used as a natural dye for Philippine textiles. To determine the concentration of the pigment isolated, each group made a standard curve using commercially available indigo dye in dimethylsulfoxide (DMSO). The following data were obtained by the two groups: Table 4. Absorbance readings of standard solutions of varying concentrations of indigo dye in DMSO. Pure DMSO 0.115 Standard solutions (ppm) Group 1 Data Group 2 Data 0.2 0.398 0.224 0.4 0.563 0.437 0.6 0.732 0.603 0.8 0.833 0.811 1.0 1.008 0.966 1. Show the constructed standard curves of the two groups with proper figure titles. 2. Which of the two groups generated a better standard curve? Justify your answer by providing the R? value for each data set. 3. The extracted pigment has an absorbance of 0.983. When a 0.2 mL-aliquot of the extract was diluted to 1.0 mL, the absorbance of the diluted solution was found to be…

Maria was tasked to determine the concentration of a Fe2(SO4)3 solution. She prepared 5 different standards of Fe2(SO4)3 using the table below as her guide. She ran the standards and the unknown solution through UV-VIS spectroscopy and recorded the absorbances of each solution. What is the slope of the line of the standard curve from the given data? 0.3194     1.1385     0.3217     2.131

4 of 15 Abs 2.0 1.5 1.0 0.5 0.25 0. 0.2 0.4 0.6 Concentration (M) With reference to the UV-Vis calibration curve reported above, calculate the concentration (Molar) of a sample whose Absorbance is 1.0. Report your answer with two significant figures.

Calculate the concentration of unknown red dye solution

The table shows a series of standard additions of Cu(II)to acidified tap water samples measured by anodic stripping voltammetry at a platinum electrode. The unknown and all standard additions were made up to the same final volume. a. What chemical reaction occurs during the stripping stage of the analysis?b. Plot absorbance as a function of the concentration of Cu (II) standard. Determine the equation of the line and the X intercept. Find the concentration of Cu(II) in the water.

This question has multiple parts. Work all the parts to get the most points. A solution of a dye was analyzed by spectrophotometry, and the following calibration data were collected. Dye Concentration Absorbance (A) at 475 nm 0.50 x 10 M 0.24 9. 1.5 x 10 M 0.36 2.5 x 10 M 3.5 x 10 M 4.5 x 10 M 0.44 0.59 0.70 a Construct a calibration plot, and determine the slope and intercept. Slope = y-intercept =

10. The concentration of haemoglobin in a blood sample was determined by spectrophotometry. A standard curve of the absorbance at 412 nm of several solutions of known haemoglobin concentrations was created. The data for the standard curve is shown below. a. Calculate the linearity coefficient (r), y-intercept and slope. b. What is the concentration (in ug/mL) of haemoglobin in your sample if the absorbance obtained at 412 nm was 0.303? Absorbance Concentration of standard solution (pg/ml) (412nm) 0.069 1 0.113 2 0.201 4 0.377 8. 0.730 16