Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 5, Problem 5.8QAP
Interpretation Introduction
(a)
Interpretation:
The signal-to-noise ratio is to be stated.
Concept introduction:
The signal and noise are two components of instrument measurements. One component is the signal, which carries the information that is of interest to the scientists and another component is the noise which refers to the unwanted fluctuations of signals.
Interpretation Introduction
(b)
Interpretation:
The number of measurements required to obtain a
Concept introduction:
The signal and noise are two components of instrument measurements. One component is the signal, which carries the information that is of interest to the scientists and another component is the noise which refers to the unwanted fluctuations of signals. For
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
7) A 25.0 ml sample containing Cu gave an instrument reading of 23.6
units (corrected for a blank). When exactly 0.500 ml of 0.0287M
Cu(NO3)2 Was added to the solution,the signal increased to 37.9
units. Calculate the molar concentration of Cu" in the sample
+2,
Indicate the relationship between 1 eV and 8065.54 cm-1.
A molecular exclusion column has a diameter of 7.8 mm and a length of 30 cm. The solid portion of the particles occupies 20% of the volume, the pores occupy 40%, and the volume between particles occupies 40%. (a) At what volume would totally excluded molecules be expected to emerge? (b) At what volume would the smallest molecules be expected? (c) A mixture of polymers of various molecular masses is eluted between 23 and 27 mL. What does this imply about the retention mechanism for these solutes on the column?
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- Explain the difference between molecular mass and nominal mass. Give the value of the molecular mass and nominal mass of benzene, C6H6.arrow_forward(B) A 0.05 mM solution of DCPIP was placed in a 1 cm spectrophotometer cuvette and a beam of light at 600nm was passed through the cuvette. The extinction coefficient for DCPIP is 3500 L/mole/cm under the specific conditions used. What proportion (as a percentage) of light would emerge from the other side of the cuvette?arrow_forwardDetermine the mean paracetamol content per tablet (in mg), using the following values: the mean absorbance 0.13, and molar absorption coefficient 9601.9 M−1 cm−1 , where the equivalent half of one tablet mass of powdered paracetamol tablets transferred is 296.4 mg and the mean paracetamol tablet weight is 599.1 mg. Give your answer to TWO decimal places (you do not need to include the units in your answer below).arrow_forward
- (b) A system with chemical potential u = 12.5 meV contains identical particles each with integer spin and has a single quantum state at energy E, = 0 meV. The temperature of the system is fixed at 290 K. To three significant figures, what is the ratio Pg/P1, where P is the probability of finding a single particle in the state Eo, and P3 is the probability of finding 3 particles in this state? P3/P (Input your answer as a number.)arrow_forwardThe student was supposed to measure the pH of a 0.1 M hydrochloric acid solution. For this purpose, he used a pH-meter and obtained the following results: 0.90, 0.93, 1.04, 1.02. Present the appropriate graphic and statistical elaboration of the performed analysis and confirm whether the applied pH-meter worked properly.arrow_forwardThe molar absorptivity for aqueous solutions of phenol at 211 nm is 6.17 x 103 L cml mol-'. Calculate the permissible range of phenol concentrations if the transmittance is to be less than 85% and greater than 7% when the measurements are made in 1.00-cm cells.arrow_forward
- The molar absorptivity for aqueous solutions of phenol at 211 nm is 6.17 × 103 L cm-1 mol-1. Calculate the permissible range of phenol concentrations if the transmittance is to be less than 85% and greater than 7% when the measurements are made in 1.00-cm cells.arrow_forwardGiven these two equations, calculate Cv for CO2 and N2 using the velocity of sound. 6. According to statistical mechanics, the contribution to Cy due to the ith vibrational mode of a molecule is c ee;/T Cv,vib,4 = R(7) ³ (e®,/T — 1)² › where Oi = hcv./kB, h is Planck's constant, and c is the speed of light in cm s-¹. v; is the vibrational frequency of the ith vibrational mode in wavenumbers (cm-¹). The quantity O, has dimensions of temperature and is sometimes referred to as the vibrational tem- perature (of the ith vibrational mode). The total vibrational contribution to the molar heat capacity for an N-atom (linear) molecule is then Cy,vib Cv,vib,i Calculate Cy for CO₂ at 300 K, assuming that the translational and rotational con- tributions are (3/2)R and R, respectively, and use the preceding equations to obtain the vibrational contribution. Four vibrational modes for CO₂ are expected (3N- 5). How- ever, three fundamental frequencies are observed at v= 667.3, 1340, and 2349.3 cm-¹.…arrow_forwardKindly answer no i, ii & iiiarrow_forward
- 3) The solution taken from a factory waste sample to prepare an internal standard contains Pb + 2 and Ag + 2, and the analysis peaks were determined as 298 mAU and 324 mAU. To analyze the unknown, a solution containing 0.150 M, 50.0 mL of Ag + 2 is put into the unknown liquid and completed to 100.0 mL. When the peaks are measured again, 670 mAU and 856 mAU signals are read from the samples. What is the concentration of Pb + 2 in the unknown liquid?arrow_forwardauDUIUance UI U.I JU ai 4JJ IIII III 1. UU CIII cuvclic. Calculate the molar absorptivity of the pigment at 453 nm? Q5) A student is tasked to determine the number of moles of H2SO4 (aq) in a 200 ml of an unknown solution. The student prepares a series of solutions with known concentrations of H2SO4 (ag) and measures the absorbance of each at an appropriate wavelength. These data are used to construct the calibration plot shown below. 1.00 0.80- 0.60 - 0.40- 0.20- 0.00- 3 x 10-4 6 x 10-4 Concentration (mol/L) If the absorbance of the unknown solution is 0.70, how many moles of H2SO4 (aq) does the 200 ml sample contain? Absorbancearrow_forwardA solution was prepared from an amount n = (0.500 ± 0.005) mol dissolved in a volume V = (250.0 ± 0.5) cm3. What is the absolute uncertainty in the concentration in units of mol dm-3?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning